Paint House LeetCode Solution

Frequently asked in Amazon Google LinkedIn Oracle Twitter
Robolox Walmart Global techViews

Problem Statement

Paint House LeetCode Solution – There is a row of n houses, where each house can be painted one of three colors: red, blue, or green. The cost of painting each house with a certain color is different. You have to paint all the houses such that no two adjacent houses have the same color.

The cost of painting each house with a certain color is represented by an n*3 cost matrix costs.

  • For example, costs[0][0] is the cost of painting house 0 with the color red; costs[1][2] is the cost of painting house 1 with the color green, and so on…

Return the minimum cost to paint all houses.

Example 1:


 costs = [[17,2,17],[16,16,5],[14,3,19]]




 Paint house 0 into blue, paint house 1 into green, paint house 2 into blue.
Minimum cost: 2 + 5 + 3 = 10.

Example 2:


 costs = [[7,6,2]]





The idea is that if I want to paint the current house Red, the previous House must be Blue or Green. If I want to paint the current house Blue, the previous house must be Red or Green. You get the idea. Thus, if we want to paint the current house red, we can take the min of (cost if we paint the prev blue, cost if we paint the prev green) + Cost of pain current red.

Or we can talk in terms of state change

  1. Previous House is Red => (Current House is Blue + cost of painting current Blue) OR Current House is Green + cost of painting current Green
  2. Previous House is Blue => Current House is Red + cost of painting current Red OR Current House is Green + cost of painting current Green
  3. Previous House is Green => Current House is Red + cost of painting current Red OR Current House is Blue + cost of painting current Blue

We’ll use an array to state the cost of painting houses[i] to be color r/g/b


Java Program of Paint House:

class Solution {
    public int minCost(int[][] costs) {
        int N = costs.length;
        int r = costs[0][0];
        int b = costs[0][1];
        int g = costs[0][2];
        for(int i = 1; i < N; i++){
            int prevR = r;
            int prevB = b;
            int prevG = g;

            r = Math.min(prevB, prevG) + costs[i][0];
            b = Math.min(prevR, prevG) + costs[i][1];
            g = Math.min(prevR, prevB) + costs[i][2];
        return Math.min(r, Math.min(b, g));

C++ Program of Paint House:

class Solution
    int minCost(std::vector<std::vector<int>> &costs)
        int N = costs.size();
        int r = costs[0][0];
        int b = costs[0][1];
        int g = costs[0][2];
        for (int i = 1; i < N; i++)
            int prevR = r;
            int prevB = b;
            int prevG = g;
            r = min(prevB,prevG) + costs[i][0];
            b = min(prevR,prevG) + costs[i][1];
            g = min(prevR,prevB) + costs[i][2];
        return min(r,min(b,g));

Complexity Analysis for Paint House LeetCode Solution

Time Complexity

The time complexity of the above code is O(n) because it depends on the input to determine how many times we loop.

Space Complexity

The space complexity of the above code is O(n) because we are using an array to store the values.

Top Interview Questions

S.No Interview Question Number of times has been asked
1Delete a node in doubly linked list2831
2Java program to find the number of Nodes in a Binary Tree2509
3Reverse a string without affecting special characters2470
4Delete a node of a linked list at given position1983
5Palindrome using Recursion1884
6Insert nodes in a linked list in a sorted way (Ascending Order)1668
7Find elements pair from array whose sum equal to number1655
8Sort Elements by Frequency of Occurrences1641
9Quick Sort1627
10Write a program to print all permutations of a given string1615
11Find Minimum Distance Between Two Numbers in an Array1479
12Create a Doubly Linked List1455
13Reverse an Array1417
14Smallest window in a string containing all characters of another string1402
15Find a Triplet That Sum to a Given Value1365
16Recursively remove all adjacent duplicates1363
17First Repeating Element1346
18Arrange Even and Odd number such that Odd comes after Even1328
19Sum of numbers in String1324
20Smallest Positive Number Missing in an Unsorted Array1292
21Check if the Elements of an Array are Consecutive1262
22Detect a loop in the Linked List1247
23Largest Sum Contiguous Subarray1235
24Quick Sort on SIngly Linked List1225
25Subarray with Given Sum1217
26Print all Possible Combinations of R Elements in a given Array of size N1212
27Recursive function to do substring search1206
28Find the Maximum Repeating Number in Array1161
29Binary Tree Level order traversal in Java1132
30Find the First and Second Smallest Elements1126
31Check if two linked lists are identical1112
32Maximum Subarray Sum using Divide and Conquer1110
33Remove characters from first string which are in second1077
34Find Leaders in an Array1065
35Swap nodes in the linked list1044
36Find the Number Occurring Odd Number of Times in an Array1009
37Find the second most frequent character997
38Arrange given Numbers to Form the Biggest Number II997
39Given a string find its first non-repeating character976
40Find Triplet in Array With a Given Sum968
41Total number of occurrences of a given item in the linked list960
42Given a sorted array and a number x, find the pair in array whose sum is closest to x959
43A Program to check if strings are rotations of each other or not956
44Print all possible words from phone digits940
45Find the Missing Number932
46Rearrange Positive and Negative Numbers Alternatively in Array928
47Longest Palindromic Substring910
48Segregate even and odd nodes in a linked list893
49Print Longest common subsequence890
50Union and Intersection of Two Linked Lists880
51Transform one string to another using minimum number of given operations874
52Check rearranged string can form a palindrome857
53Rearrange given Array in Maximum Minimum Form852
54Iterative Implementation of Quick Sort841
55Count Possible Triangles828
56Multiplication of Two Matrices809
57Check if the linked list is palindrome803
58Count of Triplets With Sum Less than Given Value802
59Rotate a Linked List801
60Stock Buy Sell to Maximize Profit797
61Insertion Sort773
62Concatenation of two strings768
63Tug of War767
64Count Number of Substrings with K Distinct Character’s763
65Print all duplicates in the input string762
66Find Nearest Greater and Smaller Element751
67The Celebrity Problem745
68Find Pythagorean Triplets from Array744
69Remove ‘b’ and ‘ac’ from a given string738
70Reverse String Without Temporary Variable738
71Find all Common Elements in Given Three Sorted Arrays735
72Remove all duplicates in an unsorted linked list716
73Find the Row with Maximum Number of 1’s712
74Find the subarray whose sum is equal to a given number X705
75Find the Peak Element from an Array705
76Remove Minimum Characters so that Two Strings Become Anagrams697
77Addition of Two Matrices692
78Find Smallest Missing Number in a Sorted Array691
79A Product Array Puzzle689
80Generate all Binary Strings Without Consecutive 1’s685
81Implement Two Stacks in an Array682
82Maximum Sum of Non Consecutive Elements679
83Maximum Product Subarray II665
84Lexicographic rank of string662
85Multiplication of Previous and Next653
86Check if Two given Matrices are Identical653
87Subtraction of Two Matrices642
88Merge K Sorted Arrays and Print Sorted Output639
89Move All the Zeros to the End of the Given Array637
90Divide a string in N equal parts634
91Online Algorithm for Checking Palindrome in a Stream629
92Form Minimum Number from Given Sequence of D’s and I’s628
93Check whether two strings are anagram of each other624
94Remove recurring digits in a given number622
95Sort a linked list that is sorted alternating ascending and descending617
96Maximum Circular Subarray Sum616
97Sort a stack using a temporary stack614
98Move last element of the Linked List at first place610
99Find the Minimum Element in a Sorted and Rotated Array610
100Subarray and Subsequence607
101First Circular Tour to Visit all the Petrol Bunks605
102Largest Subarray with Equal Number of 0’s and 1’s602
103Compare two strings(linked lists)601
104Flattening a linked list599
105Maximum Element in an Array which is Increasing and then Decreasing598
106Palindrome Permutations of a String594
107Elements Appear more than N/K times in Array588
108Palindromes in a given range585
109Print all permutations with repetition583
110Majority Element582
111Run length encoding582
112Minimum insertions to form a shortest palindrome580
113Pangram Checking580
114Minimum Characters to be Added at Front to Make String Palindrome572
115Rearrange a given linked list in-place572
116Remove all duplicates in a sorted linked list571
117Merge a linked list into another at alternate positions570
118Most repeating character in a string569
119Rotate string to get lexicographically minimum string568
120Minimum number of Merge Operations to make an Array Palindrome567
121Repeated Subsequence of Length Two or More565
122Print all anagrams together in a sequence of words560
123Reorder an Array According to the Given Indexes557
124Pancake Sorting Problem548
125Two Sum Leetcode Solution545
126Merge Overlapping Intervals II544
127Clone a Linked List with next and random pointer543
1283Sum Leetcode Solution542
129Size of The Subarray With Maximum Sum533
130Transpose of a Matrix533
131Remove Extra Spaces from a String530
132Removing Spaces from a String using stringstream528
133Remove duplicates from a string526
134Check if a given string is a rotation of a palindrome526
135Longest Palindrome can be Formed by Removing or Rearranging Characters525
136Smallest Palindrome after Replacement524
137Partition Problem524
138Maximum Sum Increasing Subsequence523
139Generate all Binary Strings from Given Pattern515
140Check whether Strings are K Distance Apart or Not515
141Length of Longest valid Substring510
142Find Zeros to be Flipped so that Number of Consecutive 1’s is Maximized507
143Insert Node in the Sorted Linked List507
144Delete Last Occurrence505
145Check if Two given Strings are Isomorphic to each other501
146Maximum difference between two elements such as larger element comes after smaller494
147Program to Toggle all Characters in a String493
148Given string is interleaving of two other strings or not489
149Count Minimum Steps to Get the given Array487
150Merge sort better than quick sort for linked lists484
151Number of Smaller Elements on Right Side483
152Check length of a String is Equal to the Number Appended at its Last481
153Find Pair with Given Difference480
154Check if all Rows of a Matrix are Circular Rotations of Each Other479
155Find nth node of the Linked list from the end476
156Longest Common Prefix using Divide and Conquer476
157Sort 0s 1s and 2s in an Array468
158Print all interleavings of given two strings467
159Find a Fixed Point in a Given Array467
160Compare Two Version Numbers465
161Reverse words in a given string462
162Merge two sorted linked lists such that merged list is in reverse order462
163Find the Subarray of given length with Least Average461
164Reorder Array Using Given Indexes460
165Print Reverse of a string (Recursion)459
166Median of Two Sorted Arrays LeetCode Solution459
167Split linked list using alternate nodes458
168Print string of odd length in ‘X’ format445
169Print all Palindromic Partitions of a String441
170Swap Kth Node from beginning with Kth Node from End440
171Find K Length Subarray of Maximum Average440
172Find Element Using Binary Search in Sorted Array439
173Find Duplicates in an Array in Most Efficient Way433
174print all palindromic partitions426
175Flatten a multilevel linked list424
176Maximum Length of Chain Pairs421
177Shortest Superstring Problem421
178Check if String Follows Order of Characters by a Pattern or not420
179Sorting a K Sorted Array418
180Sort a String According to Another String413
181Longest Span with same Sum in two Binary Arrays II404
182Reverse a Linked List in groups402
183Find a Sorted Subsequence of size 3401
184Recursively print all the sentences that can be formed from list of word lists399
185Program to add two binary digits398
186Longest Common Prefix Using Binary Search II395
187Find the two Numbers with Odd Occurrences in an Unsorted Array394
188Reverse a Singly Linked List (Iterative/Non-Recursive)393
189Caesar Cipher389
190Kth Non-repeating Character388
191Rearrange a linked list in Zig-Zag386
192Check if String can Become Empty by Recursively Deleting given Substring384
193Longest Common Prefix Word by Word Matching381
194Rotate Image by 90 degrees380
195Pancake Sorting380
196Permutations of a Given String Using STL373
197Perfect Reversible String372
198Merging Two Sorted Arrays368
199Increasing Subsequence of Length three with Maximum Product368
200Sort a linked list with 0s, 1s and 2s367
2011`s and 2`s complement of binary number367
202Construct a Maximum Sum Linked List out of two Sorted Linked Lists having some Common nodes366
203Find First non-repeating character in a string366
204Find the point where a monotonically increasing function becomes positive first time366
205Four Elements that Sum to Given363
206List items containing all characters of a given word360
207Delete N nodes after M359
208Longest Common Prefix using Character by Character Matching354
209Count Number of Occurrences in a Sorted Array354
210Palindrome string (number)350
211Split a string349
212Minimum Characters to be Removed to Make a Binary String Alternate344
213Recursive Implementation of atoi()342
214Check if a Linked list of Strings form a Palindrome341
215Print All Distinct Elements of the Array339
216Sorting the array of strings338
217Maximum occurring character in a string336
218Even Substring Count336
219Convert a String that is Repetition of a Substring of Length K335
220Valid Parentheses LeetCode Solution334
221Reverse a singly linked list recursively333
222Find the first Repeating Number in a Given Array333
223Print Shortest Path to Print a String on Screen331
224Binary Tree to Doubly linked list329
225Can we reverse a linked list in less than O(n) time ?329
226Nth Character in Concatenated Decimal String328
227Convert string1 to string2 in one edit328
228Reverse a String using Stack326
229wildcard character matching325
230Sort Elements by Frequency II325
231Lower Case To Upper Case323
232Maximum Subarray Leetcode Solution323
233Count the number of words318
234Merge Two Sorted Arrays318
235Split Four Distinct Strings317
236Find the Lost Element From a Duplicated Array315
237Find middle of the Linked List312
238Longest Common Subsequence with Permutations309
239Count the Pairs at Same Distance as in English Alphabets308
240Matrix Chain Multiplication using Dynamic Programming307
241Next Greater Element in an Array303
242Palindrome Permutation298
243Roman to Integer Leetcode Solution293
244Find Nth Node292
245Searching a node in a Binary Search Tree291
246Find All Pairs With a Given Difference290
247Triplet from three linked lists with given sum286
248Delete a Tree286
249String(represents an integer) to value284
250Reverse a String283
251Word Search Leetcode Solution283
252Reverse Bits282
253Print all Possible Ways to Break a String in Bracket Form281
254Delete a node under given conditions280
255Change Gender of a given String278
256Binary Tree278
257Sort an array of strings277
258How to Efficiently Implement k Stacks in a Single Array?277
259Count Pairs With Given Sum275
260First non Repeating Element274
261Meeting Rooms II LeetCode Solution273
262Number of sub-strings which recursively add up to 9273
263Toeplitz Matrix273
264Repeated Substring Pattern272
265Longest Common Extension271
266Move all negative elements to one side of array270
267Remove middle points in a linked list of line segments270
268N queen problem269
269Remove spaces from a string268
270Longest Palindromic Substring LeetCode Solution266
271Shuffle a given Array264
272Min Stack263
273Number of Islands LeetCode Solution260
274Cuckoo sequence program259
275Dijkstra Algorithm259
276Max stack258
277House Robber Leetcode Solution258
278Find, second, frequent, character257
279Most Frequent Element in an Array256
280Fibonacci numbers254
281Minimize the maximum difference between the heights254
282Clone a linked list with next and random pointer (Hashing)252
283Search Insert Position Leetcode Solution251
284Expression Evaluation250
285Sort linked which is sorted on absolute values250
286Sudoku Solver249
287Subset Leetcode249
288Valid Palindrome Leetcode Solution248
289Plus One Leetcode Solution247
290KMP Algorithm247
291Evaluation of Postfix Expression246
292Number Of 1 bits246
293Word Search246
294Combination Sum Leetcode Solution245
295How to Delete a Linked List245
296Reverse words in a string245
297Min Stack Leetcode Solution244
298Backspace String Compare241
299Set Matrix Zeroes238
300Rabin Karp Algorithm237
301Pair of Positive Negative Values in an Array236
302Reversing a Queue236
303Sqrt(x) Leetcode Solution236
304Merge Sorted Arrays Leetcode Solution236
305Subarray with 0 sum234
306Common elements in all rows of a given matrix233
307Tower Of Hanoi233
308Combination Sum231
309Integer to Roman Leetcode Solution230
310Contains Duplicate II Leetcode Solution230
311Delete middle element of a stack230
312Product of array except self230
313Intersection of Two Arrays II Leetcode Solution228
314String Compression228
315Pascal Triangle Leetcode228
316Reverse individual words226
317Count of index pairs with equal elements in an array225
318Construct Binary Tree from Given Inorder and Preorder Traversals225
319Minimum swaps required to bring all elements less than or equal to k together225
320Count subarrays with equal number of 1’s and 0’s225
321Segregate even and odd numbers225
322Add Binary Leetcode Solution224
323Find Top K (or Most Frequent) Numbers in a Stream224
324Bellman Ford Algorithm224
325Implementation of Deque using Doubly Linked List224
326Sliding Window Technique223
327Single Number Leetcode Solution223
328Minimum Value to Get Positive Step by Step Sum Leetcode Solution223
329Contains Duplicate222
330Palindrome Linked List Leetcode Solution221
331Arithmetic Expression Evaluation221
332Second Most Repeated Word in a Sequence221
333Sort elements by frequency221
334Find sum of non-repeating elements (distinct) elements in an array220
335Count Odd Numbers in an Interval Range Leetcode Solution220
336Pow(x, n) Leetcode Solution219
337Page Replacement Algorithms in Operating Systems219
338Postfix to Infix Conversion219
339Next Permutation218
340Group Words With Same Set of Characters218
341Design a stack that supports getMin() in O(1) time and O(1) extra space218
342Maximum Number of Balloons Leetcode Solution218
343Kruskal Algorithm217
344Longest Common Prefix Leetcode Solution216
345Smallest Subarray with k Distinct Numbers216
346Sum of minimum and maximum elements of all subarrays of size k216
347Maximum Subarray215
348Find Lucky Integer in an Array Leetcode Solution215
349Third Maximum Number Leetcode Solution215
350Scramble String215
351Permutations Leetcode Solution214
352Convex Hull Algorithm214
353Longest Substring Without Repeating Characters LeetCode Solution214
354K-th Smallest Element in a Sorted Matrix214
355Top K Frequent Words214
356Find the Town Judge Leetcode Solution213
357Sorting array using Stacks213
358Minimum operation to make all elements equal in array212
359Count subarrays having total distinct elements same as original array212
360Find Numbers with Even Number of Digits Leetcode Solution212
361Number of Good Pairs Leetcode Solution210
362Evaluate Division210
363Majority Element Leetcode Solution210
364Special Number210
365Given two unsorted arrays find all pairs whose sum is x209
366First element occurring k times in an array209
367Spiral Matrix LeetCode Solution209
368Swap Nodes in Pairs Leetcode Solutions209
369Prefix to Infix Conversion208
370Merge Two Sorted Lists Leetcode Solutions207
371Count Primes Leetcode Solutions207
372Huffman Coding207
373Minimum Path Sum207
374Check if two arrays are equal or not207
375Single Number206
376Reverse a Number Using Stack206
377Best Time to Buy and Sell Stock  II Leetcode Solution206
378Reversing the First K elements of a Queue206
379Missing Number Leetcode Solution206
380Pascal’s Triangle II Leetcode Solution206
381Search in Rotated Sorted Array Leetcode Solution205
382Minimum Absolute Difference Leetcode Solution205
383Minimum Steps to reach target by a Knight205
384Maximal Square205
385Group Anagrams205
386Sort Array by Increasing Frequency Leetcode Solution204
387House Robber II Leetcode Solution204
388Find duplicates in a given array when elements are not limited to a range204
389Maximum Distance Between two Occurrences of Same Element in Array203
390Power of Two Leetcode Solution203
391Running Sum of 1d Array Leetcode Solution203
392Palindrome Substring Queries202
393Matrix Diagonal Sum Leetcode Solution202
394How to Implement Stack Using Priority Queue or Heap?202
395Top K Frequent Elements202
396Find Minimum In Rotated Sorted Array202
397Find the first repeating element in an array of integers202
398Convert String To Int202
399Find All Numbers Disappeared in an Array Leetcode Solution202
400Unique Paths Leetcode Solution201
401Expression Contains Redundant Bracket or Not201
402Unique Paths201
403Maximum possible difference of two subsets of an array201
404Find the Closest Palindrome number201
405Fizz Buzz Leetcode201
406Check if Array Contains Contiguous Integers With Duplicates Allowed201
407Sorting using trivial hash function201
408Subarray Sum Equals k201
409Zigzag Conversion201
410How Many Numbers Are Smaller Than the Current Number Leetcode Solution200
411Sort Integers by The Number of 1 Bit Leetcode Solution200
412Smallest Element Repeated Exactly K Times200
413Average Salary Excluding the Minimum and Maximum Salary Leetcode Solution200
414Cumulative Frequency of Count of Each Element in an Unsorted Array199
415Find Number of Employees Under every Employee199
416Subset sum problem199
417Max Consecutive Ones Leetcode Solution199
418Range Sum Query 2D – Immutable Leetcode Solution199
419Leetcode Permutations199
420Find Winner on a Tic Tac Toe Game Leetcode Solution198
421Happy Number Leetcode Solution198
422Coin Change 2 Leetcode Solution198
423Length of the largest subarray with contiguous elements198
424Difference between highest and least frequencies in an array197
425Find top three repeated in array197
426Letter Case Permutation197
427Sort a stack using recursion197
428Reverse Integer197
429Print All Distinct Elements of a Given Integer Array197
430Subarray Sum Equals K LeetCode Solution197
431Decode String197
432Implement Stack and Queue using Deque197
433Monotonic Array LeetCode Solution196
434Fibonacci Number LeetCode Solution196
435Print all subarrays with 0 sum196
436Nth Catalan Number196
437LRU Cache Implementation196
438Best Time to Buy and Sell Stock III Leetcode Solution196
439Remove Duplicates from Sorted Array Leetcode Solution196
440Count Substrings with equal number of 0s, 1s and 2s195
441Sum of Subarray Ranges Leetcode Solution195
442Find The Duplicate Number194
443Generate a String With Characters That Have Odd Counts Leetcode Solution194
444Subarrays with distinct elements194
445Reverse Vowels of a String Leetcode Solution194
446Maximum Depth of Binary Tree Leetcode Solution194
447Check If N and Its Double Exist Leetcode Solution194
448Reverse a Stack Using Recursion194
449Capacity To Ship Packages Within D Days Leetcode Solution194
450Merge Two Sorted Linked Lists193
451Find Median from data Stream193
452Integer to English words193
453Kth largest element in an Array Leetcode Solutions193
454Subtract the Product and Sum of Digits of an Integer Leetcode Solution193
455Reverse Words in a String III LeetCode Solution193
456Delete a Node from linked list without head pointer192
457Shuffle the Array Leetcode Solution192
458Bipartite Graph192
459Prim’s Algorithm192
460Find the Duplicate Element192
461Trapping Rain Water Leetcode Solution192
462Find the Difference Leetcode Solution191
463Longest Common Subsequence191
464Count and Say191
465Reverse a String191
466Remove Minimum Number of Elements Such That no Common Element Exist in both Array191
467Target Sum191
468Find Common Characters Leetcode Solution190
469Find elements which are present in first array and not in second190
470Iterative Tower of Hanoi190
471Excel Sheet Column Number Leetcode Solution190
472Priority Queue Using Singly Linked List190
473Count pairs from two linked lists whose sum is equal to a given value190
474Find all pairs (a, b) in an array such that a % b = k190
475Sorting a Queue without Extra Space190
476Balanced Binary Tree Leetcode Solution190
477Edit Distance190
478Longest Common Prefix using Trie189
479Fizz Buzz189
480Floyd Warshall Algorithm189
481Concatenation of Array LeetCode Solution189
482The K Weakest Rows in a Matrix Leetcode Solution189
483Text Justification LeetCode Solution189
484Design Parking System Leetcode Solution188
485Kids With the Greatest Number of Candies Leetcode Solution188
486Minimum Moves to Equal Array Elements Leetcode Solution188
487Find First and Last Position of Element in Sorted Array Leetcode Solution188
488Degree of an array188
489Next Greater Element I Leetcode Solution188
490Reverse a linked list188
491Merge Overlapping Intervals187
492Valid Parenthesis String187
493MiniMax Algorithm187
494Prefix to Postfix Conversion187
495Top View of Binary Tree187
496Longest subarray not having more than K distinct elements187
497Word Ladder LeetCode Solution187
498Flood Fill LeetCode187
499Number of Steps to Reduce a Number to Zero Leetcode Solution187
500Kth Largest Element in a Stream Leetcode Solution187
501Multiply Strings Leetcode Solution186
502Shortest Palindrome186
503Find subarray with given sum (Handles Negative Numbers)186
504Zigzag Conversion LeetCode Solution186
505Slowest Key Leetcode Solution186
506Pair with given product186
507Find four elements that sum to a given value (Hashmap)186
508Count and Say Leetcode Solution185
509The Stock Span Problem185
510Max Area of Island185
511Postfix to Prefix Conversion185
512Jump Game Leetcode Solution185
513Find N Unique Integers Sum up to Zero Leetcode Solution185
514Priority Queue in C++185
515Convert array into Zig-Zag fashion185
516Move Zeroes LeetCode Solution184
518Find Index of Closing Bracket for a Given Opening Bracket in an Expression184
519Find any one of the multiple repeating elements in read only array184
520Length of Last Word Leetcode Solution184
521Substring With Concatenation Of All Words184
522Implement a stack using single queue184
523Mobile Numeric Keypad Problem184
524Peak Index in a Mountain Array183
525Shuffle String Leetcode Solution183
526Find distinct elements common to all rows of a matrix183
527Check if a given array contains duplicate elements within k distance from each other183
528Next Greater Frequency Element183
529Count number of triplets with product equal to given number183
530Implement Stack using Queues182
531Find missing elements of a range182
532Largest Sum Contiguous Subarray182
533Rearrange a binary string as alternate x and y occurrences182
534Longest Common Prefix using Sorting182
535Iterative Inorder Traversal of a Binary Tree182
536Intersection of Two Arrays182
537Delete Node in a Linked List Leetcode Solution181
538Contiguous Array Leetcode181
539Excel Sheet Column Title Leetcode Solution181
540Relative Sort Array Leetcode Solution181
541Last Stone Weight181
542Smallest Subarray With all Occurrences of a Most Frequent Element181
543Convert a normal BST to Balanced BST181
544Group Multiple Occurrence of Array Elements Ordered by first Occurrence180
545Change the Array into Permutation of Numbers From 1 to N180
546Valid Sudoku180
547Koko Eating Bananas Leetcode Solution180
548Minimum Bracket Reversals179
549Isomorphic Strings Leetcode Solution179
550Best Time to Buy and Sell Stock179
551N-th Tribonacci Number Leetcode Solution179
552K-th Distinct Element in an Array179
553Is Subsequence Leetcode Solution179
554First negative integer in every window of size k179
555Distribute Candies to People Leetcode Solution179
556Linked List Cycle II LeetCode Solution179
557Container with Most Water179
558Find Words That Can Be Formed by Characters Leetcode Solution178
559Assign Cookies Leetcode Solution178
560Minimum Delete Operations to make all Elements of Array Same178
561Jewels and Stones Leetcode Solution178
562Minimum Operations to convert X to Y178
563Number of Provinces Leetcode Solution178
564Implementation of Deque using circular array178
565Integer to Roman178
566Sum of Left Leaves Leetcode Solutions178
567Check for Balanced Parentheses in an Expression177
568Build Array From Permutation Leetcode Solution177
569Arrange given numbers to form the biggest number177
570Minimum Knight Moves LeetCode Solution177
571Unique Binary Search Trees177
572Island Perimeter Leetcode Solution177
573Gold Mine Problem177
574Largest Perimeter Triangle Leetcode Solution177
575Valid Anagrams177
576Shuffle an Array177
577Summary Ranges Leetcode Solution177
578Convert Sorted Array to Binary Search Tree Leetcode Solution177
579Maximum path sum in a triangle176
580Remove Linked List Elements Leetcode Solution176
581Maximum sum rectangle in a 2D matrix176
582LRU Cache LeetCode Solution176
583Count all subsequences having product less than K176
58401 Matrix LeetCode Solution176
585Combinations Leetcode Solution176
586Hamming Distance176
587Trapping Rain Water LeetCode Solution176
588Find the smallest positive integer value that cannot be represented as sum of any subset of a given array175
589Count the number of nodes at given level in a tree using BFS175
590Decode Ways175
591The Knapsack Problem175
592Rotate List Leetcode Solution175
5933Sum Closest LeetCode Solution175
594Minimum number of subsets with distinct elements174
595Shortest Path in a Grid with Obstacles Elimination LeetCode Solution174
596Minimum insertions to form a palindrome with permutations allowed174
597Maximum Distance in Array173
598Distance Between Bus Stops Leetcode Solution173
599Bubble sort using two Stacks173
600Insert Interval Leetcode Solution173
601Rotate Image LeetCode Solution173
602Maximum Number of Chocolates to be Distributed Equally Among k Students173
603Find minimum difference between any two elements173
604Same Tree LeetCode Solution173
605Minimum number of distinct elements after removing m items173
606Sieve of Eratosthenes172
607How to check if two given sets are disjoint?172
608Find if an Expression has Duplicate Parenthesis or Not172
609Stone Game LeetCode172
610Sort Characters By Frequency LeetCode Solution172
611XOR Operation in an Array Leetcode Solution172
612Find Sum of all unique sub-array sum for a given array172
613Longest Increasing Subsequence172
614Painting Fence Algorithm172
615Applications of Breadth First Search and Depth First Search171
616Reverse a stack without using extra space in O(n)171
617Word Pattern171
618License Key Formatting Leetcode Solution171
619Frog Jump Leetcode Solution171
620Permutation in String Leetcode Solution171
621Defanging an IP Address Leetcode Solution171
622Replace Elements with Greatest Element on Right Side Leetcode Solution171
623Word Wrap Problem170
624Sort Array By Parity LeetCode Solution170
625Minimum Cost to Hire K Workers170
626Find the Duplicate Number LeetCode Solution170
627Smallest Good Base170
628Remove All Occurrences of a Substring LeetCode Solution170
629K Empty Slots LeetCode170
630House Robber170
631Optimal Account Balancing LeetCode Solution169
632Tracking current Maximum Element in a Stack169
633Printing brackets in Matrix Chain Multiplication Problem169
634Segregate 0s and 1s in an Array169
635Maximum Consecutive Numbers Present in an Array169
636Distance of nearest cell having 1 in a binary matrix169
637Minimum Depth of Binary Tree Leetcode Solution169
638Isomorphic Strings169
639Non-overlapping sum of two sets169
640Best Time to Buy and Sell Stock LeetCode Solution169
641Longest Substring with At Least K Repeating Characters LeetCode Solution169
642Longest Substring with At Most K Distinct Characters LeetCode Solution168
643Merge Two Balanced Binary Search Trees168
644Coin Change Problem168
645Binary Tree Zigzag Level Order Traversal LeetCode Solution168
646Employee Free Time LeetCode Solution168
647Iterative Method to find Height of Binary Tree168
648Valid Palindrome II Leetcode Solution168
649Kth Missing Positive Number Leetcode Solution168
650Moving Average from Data Stream Leetcode Solution168
651Wiggle Sort168
652Minimum Number of Steps to Make Two Strings Anagram Leetcode Solutions167
653Reorganize String167
654Queries for counts of array elements with values in given range167
655Maximum difference between first and last indexes of an element in array167
656Find Maximum Level sum in Binary Tree167
657Sum of All Odd Length Subarrays Leetcode Solution167
658Check If It Is a Straight Line Leetcode Solution167
659Path With Maximum Minimum Value LeetCode Solution167
660Count Good Nodes in Binary Tree Leetcode Solution167
661How to Create Mergable Stack?167
662GCD Of Two Numbers166
663Best Time to Buy and Sell Stock with Cooldown Leetcode Solution166
664Rearrange an array in order – smallest, largest, 2nd smallest, 2nd largest166
665Find the Distance Value Between Two Arrays Leetcode Solution166
666Strobogrammatic Number LeetCode Solution166
667Maximum Number of Occurrences of a Substring Leetcode Solution166
668Find Largest d in Array such that a + b + c = d166
669Flipping an Image LeetCode Solution166
670Valid Palindrome165
671K Empty Slots165
672Check if a queue can be sorted into another queue using a stack165
673Reducing Dishes LeetCode Solution165
674Letter Combinations of a Phone Number165
675Delete consecutive same words in a sequence165
676Inorder Successor of a node in Binary Tree165
677Partition Labels LeetCode Solution165
678Remove Invalid Parentheses Leetcode Solution165
679Find pairs with given sum such that elements of pair are in different rows165
680Convert an array to reduced form165
681Print the Fibonacci numbers in reverse order165
682Increasing Decreasing String Leetcode Solution164
683To Lower Case Leetcode Solution164
684Factorial Trailing Zeroes Leetcode Solution164
685Delete Nth node from the end of the given linked list164
686BFS vs DFS for Binary Tree164
687Check If Two String Arrays are Equivalent Leetcode Solution164
688Number of Dice Rolls With Target Sum LeetCode Solution164
689Maximum Number of Coins You Can Get Leetcode Solution164
690Permutation Sequence LeetCode Solution163
691Recover Binary Search Tree163
692Populating Next Right Pointers in Each Node163
693Longest Increasing Path in a Matrix LeetCode Solution163
694Find Leaves of Binary Tree LeetCode Solution163
695Edit Distance LeetCode Solution163
696Lucky Numbers in a Matrix Leetcode Solution163
697Partition Array Into Three Parts With Equal Sum Leetcode Solution163
698Power of Four Leetcode Solution163
699Subset Sum Leetcode163
700Find the Smallest Divisor given a Threshold Leetcode Solution163
701Valid Perfect Square Leetcode Solution163
702Form minimum number from given sequence163
703Construct BST from given Preorder Traversal162
704Merge Two Binary Trees LeetCode Solution162
705Sort Array by Increasing Frequency Leetcode Solution162
706Unique Paths II Leetcode Solution162
707Find whether an array is subset of another array162
708Reversing a Queue using Recursion162
709Maximum Product of Two Elements in an Array Leetcode Solution162
710Ugly Number Leetcode Solution162
711Reverse Only Letters LeetCode Solution162
712String to Integer (atoi) LeetCode Solution162
713Binary Tree zigzag level order Traversal162
714Dynamic Programming Basics162
715Convert a Number to Hexadecimal Leetcode Solution161
716Decompress Run-Length Encoded List Leetcode Solution161
717Binomial Coefficient161
718Reservoir Sampling161
719Keyboard Row Leetcode Solution161
720Find the largest multiple of 3161
721Add and Search Word – Data structure design LeetCode161
722Robot Room Cleaner Leetcode Solution161
723Bulb Switcher LeetCode Solution160
724Find the node with minimum value in a Binary Search Tree160
725Perform String Shifts Leetcode160
726Restore IP Addresses Leetcode Solution160
727Majority Element II Leetcode Solution160
728Finding K closest element160
729Numbers with prime frequencies greater than or equal to k159
730Find Pair with Greatest Product in Array159
731Hamming Distance Leetcode Solution159
732Minimum Distance Between BST Nodes Leetcode Solution159
733Rank Transform of an Array Leetcode Solution159
734Snakes and Ladders LeetCode Solution159
735Word Pattern LeetCode Solution159
736Race Car LeetCode Solution159
737Check if Two Expressions With Brackets are Same159
738Find Maximum Depth of Nested Parenthesis in a String159
739Sum of f(a[i], a[j]) over all pairs in an array of n integers159
740Minimum Cost For Tickets Leetcode Solution159
741Queue based approach for first non-repeating character in a stream158
742Number of Islands II LeetCode Solution158
743Binary Tree Maximum Path Sum LeetCode Solution158
744First Unique Character in a String LeetCode Solution158
745Maximum Product of Three Numbers LeetCode Solution158
746Maximum 69 Number Leetcode Solution158
747Non-decreasing Array LeetCode Solution158
748Invert Binary Tree LeetCode Solution158
749Linked List Cycle158
750Find unique character in a string158
751Merge K Sorted Linked Lists158
752Minimum time required to rot all oranges158
753Diagonal Traversal of Binary Tree158
754Student Attendance Record I Leetcode Solution158
755Morris Traversal158
756Tiling Problem158
757Minimum Height Trees158
758Longest Span with same Sum in two Binary arrays158
759Generate all possible sorted arrays from alternate elements of two given sorted arrays158
760Best Meeting Point LeetCode Solution157
761Final Prices With a Special Discount in a Shop Leetcode Solution157
762Minimize Maximum Pair Sum in Array LeetCode Solution157
763Stack Permutations (Check if an array is stack permutation of other)157
764Maximum Depth of N-ary Tree Leetcode Solution157
765Kth ancestor of a node in binary tree157
766String Compression LeetCode Solution157
767Remove Nth Node From End of List Leetcode Solution157
768Sorted Linked List to Balanced BST157
769Find if Path Exists in Graph Leetcode Solution157
770Remove brackets from an algebraic string containing + and – operators157
771Largest subarray with equal number of 0s and 1s157
772Check If Array Pairs Are Divisible by k LeetCode Solution156
773Largest Rectangle in Histogram LeetCode Solution156
774Special Array With X Elements Greater Than or Equal X Leetcode Solution156
775Find All Duplicates in an Array LeetCode Solution156
776Symmetric Tree Leetcode Solution156
777Total Numbers With no Repeated Digits in a Range156
778Jump Game156
779Partition to K Equal Sum Subsets Leetcode Solution156
780Elements to be added so that all elements of a range are present in array156
781Maximum Length of a Concatenated String with Unique Characters Leetcode Solution156
782Search a 2D Matrix II Leetcode Solution155
783Largest rectangular sub-matrix whose sum is 0155
784Find Median from Data Stream LeetCode Solution155
785Evaluate Reverse Polish Notation LeetCode Solution155
786Program for Bridge and Torch problem155
787Count items common to both the lists but with different prices155
788Split a String in Balanced Strings Leetcode Solution155
789Transpose Graph155
790k-th missing element in increasing sequence which is not present in a given sequence155
791Maximum Difference Between Increasing Elements LeetCode Solution155
792Base 7 Leetcode Solution154
793Longest Subarray Having Count of 1s One More than Count of 0s154
794Check for Palindrome after every character replacement Query154
795Print a Binary Tree in Vertical Order154
796Search in a Binary Search Tree Leetcode Solution154
797Valid Number154
798Growable array based stack154
799Interval Tree154
800Circular Queue154
801Number of NGEs to the Right154
802Sort an array according to the order defined by another array154
803N-Queens LeetCode Solution154
804Minimum Jumps to Reach Home LeetCode Solution154
805Course Schedule II – LeetCode154
806Deletion in a Binary Tree154
807One Edit Distance LeetCode Solution153
808Count quadruples from four sorted arrays whose sum is equal to a given value x153
809Minimum number of jumps to reach end153
810Number Complement Leetcode Solution153
811Nearest Exit from Entrance in Maze LeetCode Solution153
812Merge Sorted Array LeetCode Solution153
813Minimum swaps to make sequences increasing153
814Reorder Data in Log Files LeetCode Solution153
815Nested List Weight Sum II LeetCode Solution153
816Sort Array By Parity II Leetcode Solution153
817Last Stone Weight II LeetCode Solution153
818Spiral Matrix II Leetcode Solution153
819String comparison containing wildcards153
820Get Maximum in Generated Array Leetcode Solution153
821Minimum Time Visiting All Points Leetcode Solution153
822Remove Duplicates from Sorted List II153
823Remove Duplicates from Sorted List LeetCode Solution152
824Iterative Preorder Traversal152
825Maximum Profit in Job Scheduling Leetcode Solution152
826Relative Ranks Leetcode Solution152
827Find all triplets with zero sum152
828A Space Optimized DP solution for 0-1 Knapsack Problem152
829Maximum size subarray sum equals k152
830Regular Expression Matching152
831Find Maximum Sum Possible Equal Sum of Three Stacks152
832Priority Queue using doubly linked list152
833Subarray Product Less Than K LeetCode Solution152
834Convert BST to Min Heap152
835Crawler Log Folder Leetcode Solution152
836Insert into a Binary Search Tree Leetcode Solution151
837Form Minimum Number From Given Sequence151
838LCS (Longest Common Subsequence) of three strings151
839Can Place Flowers LeetCode Solution150
840Valid Parentheses Leetcode Solution150
841Sum of nearest smaller and greater number150
842Subset with sum divisible by m150
843Minimum Number of Taps to Open to Water a Garden LeetCode Solution150
844Sort Colors150
845Alien Dictionary LeetCode Solution150
846Make Two Arrays Equal by Reversing Sub-arrays Leetcode Solution150
847Maximum Nesting Depth of the Parentheses Leetcode Solution150
848Partition List Leetcode Solution150
849Check if a given array can represent Preorder Traversal of Binary Search Tree150
850Brick Wall LeetCode Solution150
851Minimum Swaps to Make Strings Equal Leetcode Solution150
852Given an Array of Pairs Find all Symmetric Pairs in it150
853Sequences of given length where every element is more than or equal to twice of previous150
854Level order Traversal in Spiral Form150
855Tree Traversal (Preorder, Inorder & Postorder)150
856Binary Search Tree Search and Insertion150
857Design a Stack With Increment Operation Leetcode Solution150
858Path with maximum average value150
859Find the subarray with least average150
860Friends Pairing Problem150
861Top K Frequent Words LeetCode Solution150
862Balanced Expression with Replacement149
863Find the Only Repetitive Element Between 1 to N-1149
864Find All Possible Recipes from Given Supplies LeetCode Solution149
865Guess Number Higher or Lower LeetCode Solution149
866Identify and Mark Unmatched Parenthesis in an Expression149
867Number of Days Between Two Dates LeetCode Solution149
868Subsequence of Size K With the Largest Even Sum LeetCode Solution149
869Count Negative Numbers in a Sorted Matrix LeetCode Solution149
870Sorted Array to Balanced BST149
871Missing Element in Sorted Array LeetCode Solution149
872Matrix Chain Multiplication149
873Permutation Coefficient149
874Minimum Sum Path in a Triangle149
875Count Distinct Elements in Every Window of Size K149
876Range LCM Queries149
877Check whether a given Binary Tree is Complete or not149
878Brightest Position on Street LeetCode Solution149
879Clone Graph LeetCode Solution149
880Range sum queries without updates148
881Repeated Substring Pattern LeetCode Solution148
882GCDs of given index ranges in an array148
883Count ways to reach the nth stair using step 1, 2 or 3148
884Union and Intersection of two Linked Lists148
885Time Based Key-Value Store LeetCode Solution148
886Destination City Leetcode Solution148
887An Interesting Method to generate Binary Numbers from 1 to n148
888Best Time to Buy and Sell Stock with Transaction Fee Leetcode Solution148
889Check if stack elements are pairwise consecutive148
890Find Common Characters Leetcode Solution148
891Diagonal Traverse LeetCode Solution148
892K’th Largest Element in BST when modification to BST is not allowed147
893Check if an Array is Stack Sortable147
894Find distance between two nodes of a Binary Tree147
895Lemonade Change Leetcode Solution147
896Guess Number Higher or Lower II147
897Delete And Earn147
898Rearrange an Array Such that arr[i] is equal to i147
899Spiral Matrix III LeetCode Solution147
900BFS for Disconnected Graph147
901Distinct adjacent elements in an array147
902Three way partitioning of an array around a given range147
903Averages of Levels in Binary Tree147
904Design Browser History LeetCode Solution147
905Shortest Word Distance Leetcode Solution147
906Water Bottles Leetcode Solution147
907Insert Delete GetRandom147
908Convert Sorted List to Binary Search Tree147
909Diagonal Traversal LeetCode Solution147
910Daily Temperatures Leetcode Solution146
911Minimum sum of multiplications of n numbers146
912Set Matrix Zeroes Leetcode Solution146
913Least Number of Unique Integers after K Removals Leetcode Solution146
914Rearrange Spaces Between Words Leetcode Solution146
915Robot Bounded In Circle LeetCode Solution146
916Construct Complete Binary Tree from its Linked List Representation146
917Queue using Stacks146
918Maximum Score After Splitting a String Leetcode Solution146
919Special Positions in a Binary Matrix Leetcode Solution146
920Vertical sum in a given binary tree146
921Number of Distinct Islands Leetcode Solution145
922Check if the given array can represent Level Order Traversal of Binary Search Tree145
923Iterative Postorder Traversal Using Two Stacks145
924Dividing Array into Pairs With Sum Divisible by K145
925Rearrange Array such that arr[i] >= arr[j] if i is even and arr[i] <= arr[j] if i is odd and j < i145
926Construct the Rectangle Leetcode Solution145
927Find all permuted rows of a given row in a matrix145
928Alien Dictionary145
929Split Array Into Consecutive Subsequences144
930A program to check if a binary tree is BST or not144
931Lexicographical Numbers Leetcode Solution144
932Binary Tree Longest Consecutive Sequence LeetCode Solution144
933Construct BST from its given Level Order Traversal144
934Maximum Subarray Sum Excluding Certain Elements144
935Merge Two Sorted Lists Leetcode144
936Count Subarrays with Same Even and Odd Elements144
937Print Fibonacci sequence using 2 variables144
9393 Sum144
940Palindrome Partitioning Leetcode Solution144
941Largest area rectangular sub-matrix with equal number of 1’s and 0’s144
942Difference Array | Range update query in O(1)143
943Maximum Frequency Stack Leetcode Solution143
944Create Maximum Number143
945Remove Duplicates from Sorted List II LeetCode Solution143
946Queries for GCD of all numbers of an array except elements in a given range143
947Sliding Window Maximum143
948Strongly Connected Component143
949Minimum Height Trees LeetCode Solution143
950Stone Game II Leetcode143
951Check if any two intervals overlap among a given set of intervals143
952Three Consecutive Odds Leetcode Solution143
953Median of Two Sorted Arrays143
954Longest Palindromic Subsequence143
955Number of Equivalent Domino Pairs Leetcode Solution143
956Maximize Sum of Array after K Negations Leetcode Solution142
957All Unique Triplets that Sum up to a Given Value142
958My Calendar I LeetCode Solution142
959Analyze User Website Visit Pattern LeetCode Solution142
960Collect maximum points in a grid using two traversals142
961Trim a Binary Search Tree142
962Infix to Postfix142
963Can Make Arithmetic Progression From Sequence Leetcode Solution142
964Maximum Product Subarray141
965Count Primes in Ranges141
966Binary array after M range toggle operations141
967Find the Difference Leetcode Solution141
968Merging Intervals141
969Unique Paths II141
970Find postorder traversal of BST from preorder traversal141
971Shuffle 2n integers as without using extra space141
972Count Submatrices With All Ones LeetCode Solution141
973Minesweeper LeetCode Solution141
974Intersection of Two Linked Lists LeetCode Solution141
975Kth Smallest Element in a BST Leetcode Solution141
976K Closest Points to Origin Leetcode Solution140
977The Painter’s Partition Problem140
978Height of a generic tree from parent array140
979Longest Nice Substring LeetCode Solution140
980Length of Longest Fibonacci Subsequence140
981Climbing stairs140
982Word Break140
983Find Maximum of Minimum for Every Window Size in a Given Array140
984Sign of the Product of an Array LeetCode Solution140
985Symmetric Tree140
986Count pair with Given Sum140
987Reverse Nodes in K-Group140
988Pattern Occurrences using Stack140
989Boundary Traversal of binary tree140
990Count subarrays where second highest lie before highest140
991Largest divisible pairs subset139
992Friends Of Appropriate Ages LeetCode Solution139
993Palindrome Partitioning139
994Level Order Traversal of Binary Tree139
995Product of Array Except Self LeetCode Solution139
996Binary Search Tree Delete Operation139
997Largest Substring Between Two Equal Characters Leetcode Solution139
998Newman-Conway Sequence139
999Largest Number Leetcode Solution139
1000Check If a Word Occurs As a Prefix of Any Word in a Sentence Leetcode Solution139
1001Asteroid Collision LeetCode Solution139
1002Valid Boomerang Leetcode Solution139
1003Maximum length subsequence with difference between adjacent elements as either 0 or 1139
1004Number Of Longest Increasing Subsequence138
1005Graph Valid Tree LeetCode Solution138
1006The Maze III LeetCode Solution138
1007Boolean Parenthesization Problem138
1008Maximum Number of Ways to Partition an Array LeetCode Solution138
1009Scramble String LeetCode Solution138
1010Find Duplicate Subtrees138
1011Double the first element and move zero to end138
1012Maximum Length of Repeated Subarray138
1013Insertion in a Binary Tree138
1014Maximum subsequence sum such that no three are consecutive138
1015Segment Tree138
1016Merge Sort138
1017Find number of pairs in an array such that their XOR is 0138
1018Shortest Completing Word Leetcode Solution138
1019Breadth First Search (BFS) for a Graph138
1020Minimum Index Sum of Two Lists138
1021Construction of Longest Increasing Subsequence (N log N)138
1022Rearrange array such that even positioned are greater than odd137
1023Maximum Product of Indexes of Next Greater on Left and Right137
1024Maximum Sum of 3 Non-Overlapping Subarrays137
1025Kill Process LeetCode Solution137
1026Depth First Search (DFS) for a Graph137
1027Construct Binary Tree from given Parent Array representation137
1028Binary Search Tree137
1029Number of palindromic paths in a matrix137
1030Compute nCr % p137
1031Ugly Numbers137
1032Rearrange an array such that ‘arr[j]’ becomes ‘i’ if ‘arr[i]’ is ‘j’137
1033Decrypt String from Alphabet to Integer Mapping Leetcode Solution137
1034Longest subsequence such that difference between adjacents is one137
1035Find the First Circular Tour that visits all the Petrol Pumps137
1036String Matching in an Array Leetcode Solution137
1037First missing positive136
1038Partition Equal Subset Sum136
1039Morris Inorder Traversal136
1040Build an Array With Stack Operations Leetcode Solution136
1041Make The String Great Leetcode Solution136
1042Iterative Depth First Traversal of Graph136
1043Count minimum steps to get the given desired array136
1044Maximum weight transformation of a given string136
1045Serialize and Deserialize Binary Tree136
1046Design Hit Counter LeetCode Solution136
1047K maximum sums of overlapping contiguous sub-arrays136
1048Level order traversal using two Queues136
1049Next Greater Element III LeetCode Solution136
1050Invalid Transactions LeetCode Solution135
1051Balanced Binary Tree135
1052Add two numbers135
1053Kth Smallest Element in a Sorted Matrix LeetCode Solution135
1054Available Captures for Rook Leetcode Solution135
1055Advantages of BST over Hash Table135
1056Custom Sort String Leetcode Solution135
1057Bitwise AND of Numbers Range LeetCode Solution135
1058Maximum difference between frequency of two elements such that element having greater frequency is also greater135
1059Employee Importance LeetCode Solution134
1060Validate Binary Search Tree134
1061Path Sum II LeetCode Solution134
1062Count pairs from two sorted arrays whose sum is equal to a given value x134
1063Super Ugly Number133
1064Find a Peak Element II LeetCode Solution133
1065Generate Parentheses Leetcode Solution133
1066Move all negative elements to end in order with extra space allowed133
1067Ugly Number II LeetCode Solution133
1068Recover Binary Search Tree Leetcode Solution133
1069Defanging an IP Address LeetCode Solution133
1070Minimum Size Subarray Sum133
1071Implement Trie (Prefix Tree) Leetcode Solution133
1072Lowest Common Ancestor133
1073Determine Whether Matrix Can Be Obtained By Rotation LeetCode Solution133
1074Rearrange array such that even index elements are smaller and odd index elements are greater133
1075Remove Duplicates from Sorted Array II Leetcode Solution132
1076Regular Expression Matching Regular Expression Matching LeetCode Solution132
1077Populating Next Right Pointers in Each Node Leetcode Solution132
1078Subarrays with K Different Integers Leetcode Solution132
1079Binary Tree Right Side View LeetCode Solution132
1080Number of Closed Islands Leetcode Solution132
1081Root to Leaf path with target sum Leetcode Solutions132
1082Find whether a subarray is in form of a mountain or not132
1083Search in Sorted Rotated Array132
1084Largest BST Subtree LeetCode Solution132
1085Find Peak Element132
1086Types of Binary Tree131
1087Smallest Common Region Leetcode Solution131
1088Longest Bitonic Subsequence131
1089Combination Sum IV LeetCode Solution131
1090Day of the Year Leetcode Solution131
1091Count Largest Group Leetcode Solution131
1092Remove Palindromic Subsequences Leetcode Solution131
1093Number of Students Doing Homework at a Given Time Leetcode Solution131
1094Find Smallest Range Containing Elements from k Lists131
1095Binary Tree Data Structure130
1096Clone a Binary Tree with Random Pointers130
1097Kth Smallest Product of Two Sorted Arrays LeetCode Solution130
1098Minimum Absolute Difference in BST Leetcode Solution130
1099Serialize and Deserialize Binary Tree LeetCode Solution130
1100Consecutive Characters LeetCode Solution130
1101Maximize Distance to Closest Person LeetCode Solution130
1102Print all triplets in sorted array that form AP130
1103Number of siblings of a given Node in n-ary Tree130
1104Palindrome Permutation LeetCode Solution129
1105Distinct Subsequences129
1106Remove duplicates from sorted array129
1107Sum of Even Numbers After Queries129
1108Convert BST into a Min-Heap without using array129
1109Path Sum129
1110Construct K Palindrome Strings LeetCode Solution129
1111Level of Each node in a Tree from source node129
1112Find the minimum distance between two numbers129
1113Find maximum difference between nearest left and right smaller elements129
1114Next Permutation Leetcode Solution129
1115Cutting a Rod129
1116Print Next Greater Number of Q queries129
1117Increasing Triplet Subsequence LeetCode Solution129
1118Constant time range add operation on an array128
1119Bottom View of a Binary Tree128
1120Minimum sum of squares of character counts in a given string after removing k characters128
1121Third Maximum Number Leetcode Solution128
1122Maximum Product Subarray128
1123Construct Binary Tree from Preorder and Postorder Traversal LeetCode Solution128
1124Find Three Element From Different Three Arrays Such That a + b + c = sum128
1125Iterative method to find ancestors of a given binary tree128
1126Valid Tic-Tac-Toe State LeetCode Solution128
1127Divisible Pairs Counting128
1128Mean of Array After Removing Some Elements Leetcode Solution128
1129Reformat The String Leetcode Solution128
1130Maximum Product of Splitted Binary Tree LeetCode Solution127
1131Prime Palindrome LeetCode Solution127
1132Print Right View of a Binary Tree127
1133Longest Increasing Consecutive Subsequence127
1134Minimum Score Triangulation of Polygon Leetcode Solution127
1135Write Code to Determine if Two Trees are Identical127
1136Delete Nodes and Return Forest Leetcode Solution127
1137Thousand Separator Leetcode Solution127
1138Longest Subarray of 1’s After Deleting One Element LeetCode Solution127
1139Products of ranges in an array127
1140Queries for Number of Distinct Elements in a Subarray126
1141Search Insert Position126
1142Cells with Odd Values in a Matrix LeetCode Solution126
1143Find maximum length Snake sequence126
1144Swap Nodes In Pairs126
1145Moser-de Bruijn Sequence126
1146Palindromic Substrings Leetcode Solution126
1147Search an Element in Sorted Rotated Array126
1148Merge two BSTs with limited extra space125
1149Red-Black Tree Introduction125
1150Topological Sorting125
1151Maximum Binary Tree125
1152Subset Sum Problem in O(sum) space125
1153Closest Binary Search Tree Value Leetcode Solution124
1154Kth Smallest Number in Multiplication Table Leetcode Solution124
1155Print modified array after executing the commands of addition and subtraction124
1156Find Two Non-overlapping Sub-arrays Each With Target Sum LeetCode Solution124
1157Diameter of N-Ary Tree LeetCode Solution124
1158Check Array Formation Through Concatenation Leetcode Solution124
1159Maximize sum of consecutive differences in a circular array124
1160Transform a BST to Greater sum Tree124
1161Priority Queue124
1162Bus Routes Leetcode Solution124
1163Decision Tree123
1164Golomb sequence123
1165Search Suggestions System LeetCode Solution123
1166Web Crawler LeetCode Solution123
1167Find Largest Value in Each Tree Row LeetCode Solution123
1168Possible Bipartition LeetCode Solution123
1169Minimum Sideway Jumps LeetCode Solution123
1170Remove Max Number of Edges to Keep Graph Fully Traversable Leetcode Solution123
1171K’th Largest element in BST using constant extra space122
1172Longest Repeated Subsequence122
1173Find a sorted subsequence of size 3 in linear time122
1174Find the smallest binary digit multiple of given number122
1175Binary Tree to Binary Search Tree Conversion122
1176Minimum Cost to Move Chips to The Same Position LeetCode Solution122
1177Count even length binary sequences with same sum of first and second half bits122
1178Compare Strings by Frequency of the Smallest Character Leetcode Solution122
1179Rotate Array122
1180Minimum Moves to Equal Array Elements LeetCode Solution122
1181Decrease Elements To Make Array Zigzag LeetCode Solution121
1182Reverse a Path in BST using Queue121
1183Graph and its representation121
1184Factorial Trailing Zeroes LeetCode Solution121
1185First Bad Version121
1186Given a binary tree, how do you remove all the half nodes?121
1187Matchsticks to Square Leetcode Solution121
1188Swapping Nodes in a Linked List Leetcode Solution121
1189Maximum sum of pairs with specific difference120
1190Maximum number of segments of lengths a, b and c120
1191Contiguous Array LeetCode Solution120
1192Filter Restaurants by Vegan-Friendly, Price and Distance Leetcode Solution120
1193Lowest Common Ancestor in Binary Search Tree120
1194Queue Reconstruction by Height120
1195Reformat Date LeetCode Solution120
1196Count Pairs Whose Products Exist in Array120
1197Number of Orders in the Backlog Leetcode Solution120
1198Convert Sorted Array to Binary Search Tree LeetCode Solutions120
1199Path Crossing Leetcode Solution119
1200Concatenation of Array LeetCode Solution119
1201Range Queries for Longest Correct Bracket Subsequence119
1202Closest Leaf in a Binary Tree LeetCode Solution119
1203Sum of Left Leaves LeetCode Solution119
1204Valid Triangle Number119
1205How to print maximum number of A’s using given four keys119
1206Maximum sum bitonic subarray119
1207Maximum Depth Of Binary Tree119
1208BST to a Tree with Sum of all Smaller Keys118
1209Champagne Tower LeetCode Solution118
1210Moving Stones Until Consecutive Leetcode Solution118
1211Minimum Swaps To Make Sequences Increasing LeetCode Solution118
1212Lowest Common Ancestor of a Binary Tree Leetcode Solution118
1213LRU Cache Leetcode Solution117
1214Array Queries for multiply replacements and product117
1215Write a function to get the intersection point of two Linked Lists117
1216Kth Smallest Element in a BST117
1217Perfect Squares LeetCode Solution117
1218Integer Break LeetCode Solution117
1219Guess The Word117
1220Divide Two Integers Leetcode Solution117
1221Check if all levels of two Binary Tree are anagrams or not116
1222Replace two consecutive equal values with one greater116
1223Mean of range in array116
1224Convert Integer to the Sum of Two No-Zero Integers Leetcode Solution116
1225Valid Perfect Square LeetCode Solution116
1226Maximum Value at a Given Index in a Bounded Array LeetCode Solution116
1227Maximum sum of a path in a Right Number Triangle116
1228Queries on Probability of Even or Odd Number in given Ranges116
1229Flatten 2D Vector LeetCode Solution116
1230Maximize Elements Using Another Array116
1231Sliding Window Median Leetcode Solution116
1232Power of Two115
1233Arithmetic Slices II – Subsequence LeetCode Solution115
1234Maximum Array from Two given Arrays Keeping Order Same115
1235Design Skiplist LeetCode Solution115
1236Range Sum Query using Sparse Table115
1237New 21 Game115
1238Graph Cloning114
1239Check if each internal node of a BST has exactly one child114
1240Bold Words in String LeetCode Solution114
1241Find Minimum in Rotated Sorted Array II LeetCode Solution114
1242Longest Common Prefix Using Word by Word Matching114
1243The kth Factor of n Leetcode Solution114
1244Check Completeness of a Binary Tree LeetCode Solution114
1245Check for Identical BSTs without building the trees114
1246Print modified array after multiple array range increment operations113
1247Parallel Courses II LeetCode Solution113
1248Contiguous Array113
1249Count Subsets Having Distinct Even Numbers113
1250Largest Plus Sign Leetcode Solution113
1251Find k-th smallest element in BST (Order Statistics in BST)113
1252Maximum Product Subarray113
1253Print n terms of Newman-Conway Sequence112
1254Find minimum number of merge operations to make an array palindrome112
1255Symmetric Tree LeetCode Solution Leetcode Solution112
1256Print Ancestors of a Given Binary Tree Node Without Recursion112
1257Merge k Sorted Lists Leetcode Solution111
1258Minimum Remove to Make Valid Parentheses LeetCode Solution111
1259Missing Number111
1260Image Overlap LeetCode Solution111
1261Check if two nodes are on the same path in a Tree111
1262Number of elements less than or equal to a given number in a given subarray110
1263Count and Toggle Queries on a Binary Array110
1264Excel Sheet Column Title LeetCode Solution110
1265Verify Preorder Serialization of a Binary Tree110
1266Smallest Range II Leetcode Solution110
1267Next greater element109
1268Orderly Queue LeetCode Solution108
1269Check If a String Can Break Another String Leetcode Solution108
1270Minimum Time to Collect All Apples in a Tree LeetCode Solution108
1271Palindrome Partitioning108
1272Min Cost Climbing Stairs LeetCode Solution107
1273Koko Eating Bananas LeetCode Solution107
1274Different Ways to Add Parentheses Leetcode Solution107
1275Longest Substring Without Repeating Characters Leetcode Solution106
1276Peeking Iterator LeetCode Solution106
1277Check in binary array the number represented by a subarray is odd or even106
1278Largest Submatrix With Rearrangements LeetCode Solution106
1279Newman–Shanks–Williams prime105
1280Check if X can give change to every person in the Queue105
1281Queries for Decimal Values of Subarrays of a Binary Array104
1282Merge Sorted Array104
1283Range Minimum Query (Square Root Decomposition and Sparse Table)103
1284Encoded String With Shortest Length LeetCode Solution102
1285Array Nesting Leetcode Solution102
1286Find maximum average subarray of k length101
1287Arranging Coins Leetcode Solution101
1288Maximum Sum Increasing Subsequence101
1289Convert a BST to a Binary Tree such that sum of all greater keys is added to every key100
1290Check given array of size n can represent BST of n levels or not100
1291Maximum product of an increasing subsequence100
1292Number of indexes with equal elements in given range100
1293Minimum Total Space Wasted With K Resizing Operations LeetCode Solution99
1294Convert to Base -2 LeetCode Solution99
1295Minimum Number of People to Teach LeetCode Solution98
1296Continuous Subarray Sum LeetCode Solution98
1297Random Pick Index LeetCode Solution98
1298Find the Winner of the Circular Game LeetCode Solution98
1299Reach a Number LeetCode Solution97
1300Add Two Numbers II Leetcode Solution97
1301Jump Game IV LeetCode Solution97
1302Binary Tree to Binary Search Tree Conversion using STL set97
1303Number of Subsequences That Satisfy the Given Sum Condition LeetCode solution96
1304Vertical Order Traversal of Binary Tree LeetCode Solution96
1305Queries on XOR of greatest odd divisor of the range96
1306Palindrome Number LeetCode Solution95
1307Minimum Possible Integer After at Most K Adjacent Swaps On Digits LeetCode Solution94
1308Insert Delete GetRandom O(1) Leetcode Solution94
1309Design Underground System Leetcode Solution90
1310Print Maximum Length Chain of Pairs89
1311Detect Capital Leetcode Solution88
1312Shifting Letters LeetCode Solution88
1313Design A Leaderboard Leetcode Solution87
1314Substring with Concatenation of All Words Leetcode Solution84
1315Count Sub Islands LeetCode Solution83
1316Top K Frequent Elements LeetCode Solution83
1317Minimum Swaps to Group All 1’s Together Leetcode Solution83
1318Minimum Path Sum Leetcode Solution81
1319Binary Tree Inorder Traversal LeetCode Solution81
1320Longest Common Subsequence LeetCode Solution78
1321Maximum Population Year LeetCode Solution77
1322Odd Even Linked List Leetcode Solution77
1323Find the Town Judge LeetCode Solution77
1324Best Meeting Point LeetCode Solution76
1325Decode String Leetcode Solution76
1326Find the Town Judge LeetCode Solution76
1327Shortest Unsorted Continuous Subarray LeetCode Solution75
1328Sum Root to Leaf Numbers LeetCode Solution74
1329Rectangle Overlap LeetCode Solution71
1330Maximum Population Year LeetCode Solution71
1331Design Add and Search Words Data Structure LeetCode Solution71
1332Flatten Binary Tree to Linked List LeetCode Solution69
1333Score of Parenthesis LeetCode Solution68
1334Stone Game IV LeetCode Solution67
1335Insert into a Sorted Circular Linked List LeetCode Solution67
1336Range Sum Query 2D – Immutable LeetCode Solution66
1337Reveal Cards In Increasing Order Leetcode Solution65
1338Valid Triangle Number LeetCode Solution64
1339Is Graph Bipartite? LeetCode Solution63
1340Divide Chocolate LeetCode Solution57
1341Step-By-Step Directions From a Binary Tree Node to Another LeetCode Solution52
1342Reverse Integer Leetcode Solution47
1343Range Sum of BST LeetCode Solution46
1344Sort Colors LeetCode Solution43
1345Find K Closest Elements LeetCode Solution43
1346Maximum Side Length of a Square with Sum Less than or Equal to Threshold LeetCode Solution40
1347Rotate String LeetCode Solution40
1348Excel Sheet Column Number LeetCode Solution39
1349H-Index Leetcode Solution20
1350Maximum Size Subarray Sum Equals k Leetcode Solution20
1351High Five LeetCode Solution19
1352Camelcase Matching Leetcode Solution18
1353Monotonic Array Leetcode Solution16
1354Group Shifted Strings Leetcode Solution13
1355Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution12
1356Peak Index in a Mountain Array LeetCode Solution11
1357Unique Binary Search Trees LeetCode Solution11
1358Valid Triangle Number LeetCode Solution10
1359Isomorphic Strings LeetCode Solution9
1360Next Greater Element I Leetcode Solution9
1361Closest Binary Search Tree Value II LeetCode Solution8
1362Flatten Binary Tree to Linked List LeetCode Solution8
1363Minimum Number of Arrows to Burst Balloons LeetCode Solution8
1364Swim in Rising Water LeetCode Solution7
1365Sentence Screen Fitting LeetCode Solution7
1366Paint House LeetCode Solution
Translate »