Continuous Subarray Sum LeetCode Solution

Difficulty Level Medium
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Problem Statement

Continuous Subarray Sum LeetCode Solution – Given an integer array nums and an integer k, return true if nums has a continuous subarray of the size of at least two whose elements sum up to a multiple of k, or false otherwise.

An integer x is a multiple of k if there exists an integer n such that x = n * k0 is always a multiple of k


Example 1:

Continuous Subarray Sum LeetCode SolutionPin


 nums = [23,2,4,6,7], k = 6




 [2, 4] is a continuous subarray of size 2 whose elements sum up to 6.

Example 2:


 nums = [23,2,6,4,7], k = 6




 [23, 2, 6, 4, 7] is an continuous subarray of size 5 whose elements sum up to 42.
42 is a multiple of 6 because 42 = 7 * 6 and 7 is an integer.

Example 3:


 nums = [23,2,6,4,7], k = 13




  • 1 <= nums.length <= 105m
  • 0 <= nums[i] <= 109
  • 0 <= sum(nums[i]) <= 231 - 1
  • 1 <= k <= 231 - 1



  1. this problem is the same as Subarray sum equals K with some modification
  2. We need a subarray say from i to j such that sum of all elements is divisible by k.
  3. We make a prefix sum array where prefixSum[i] is the (sum of first i elements)%k.
  4. for some prefixSum(0,j) , we need to check if there exist some prefixSum(0,i) such that both are equal.
  5. if they both are equal then it means the subarray i+1 to j has sum==0 so this subarray is divided by k


Continuous Subarray Sum C++ Leetcode Solution:

class Solution {
    bool checkSubarraySum(vector<int>& nums, int k) {
        int n=nums.size();
        vector<int> arr(n,0);
      unordered_map<int,int> mp;
        for(int i=1;i<n;i++)
           if(arr[i]==0)return true;

                int idx=mp[arr[i]];
                return true;
        return false;

Continuous Subarray Sum Java Leetcode Solution:

class Solution {
    public boolean checkSubarraySum(int[] nums, int k) {
    Map<Integer, Integer> map = new HashMap<>(){{put(0,-1);}};;
    int runningSum = 0;
    for (int i=0;i<nums.length;i++) {
        runningSum += nums[i];
        if (k != 0) runningSum %= k; 
        Integer prev = map.get(runningSum);
        if (prev != null) {
            if (i - prev > 1) return true;
        else map.put(runningSum, i);
    return false;

Complexity Analysis :

Time Complexity:

The Time Complexity of the above solution is O(n) where n = the size of the input array since we traversed the entire array once.

Space Complexity:

The Space Complexity of the above solution is O(n) for prefix sum and O(k) for hashmap.

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585Shortest Path in a Grid with Obstacles Elimination LeetCode Solution168
586Change the Array into Permutation of Numbers From 1 to N168
587Minimum number of distinct elements after removing m items167
588Rotate List Leetcode Solution167
589Unique Binary Search Trees167
5903Sum Closest LeetCode Solution167
591K Empty Slots LeetCode167
592Decode Ways167
593Same Tree LeetCode Solution166
594Combinations Leetcode Solution166
595LRU Cache LeetCode Solution166
596How to check if two given sets are disjoint?166
597Minimum Knight Moves LeetCode Solution166
598Distance Between Bus Stops Leetcode Solution166
599Sieve of Eratosthenes166
600XOR Operation in an Array Leetcode Solution165
601Maximum difference between first and last indexes of an element in array165
602Permutation in String Leetcode Solution165
603Rotate Image LeetCode Solution165
604Find minimum difference between any two elements165
605Frog Jump Leetcode Solution164
606Segregate 0s and 1s in an Array164
607Remove All Occurrences of a Substring LeetCode Solution164
608Sort Characters By Frequency LeetCode Solution164
609Word Pattern164
610Printing brackets in Matrix Chain Multiplication Problem164
611Maximum Distance in Array164
612Best Time to Buy and Sell Stock LeetCode Solution164
613Find Sum of all unique sub-array sum for a given array164
614Minimum number of subsets with distinct elements164
615Stone Game LeetCode163
616Sort Array By Parity LeetCode Solution163
617Minimum Depth of Binary Tree Leetcode Solution163
618Find if an Expression has Duplicate Parenthesis or Not163
619Painting Fence Algorithm163
620Word Wrap Problem163
621Smallest Good Base163
622Minimum insertions to form a palindrome with permutations allowed163
623Coin Change Problem162
624Replace Elements with Greatest Element on Right Side Leetcode Solution162
625Defanging an IP Address Leetcode Solution162
626License Key Formatting Leetcode Solution162
627Applications of Breadth First Search and Depth First Search162
628Distance of nearest cell having 1 in a binary matrix162
629Find the Duplicate Number LeetCode Solution162
630Maximum Number of Chocolates to be Distributed Equally Among k Students162
631Rearrange an array in order – smallest, largest, 2nd smallest, 2nd largest161
632Tracking current Maximum Element in a Stack161
633Kth Missing Positive Number Leetcode Solution161
634House Robber161
635Minimum Cost to Hire K Workers161
636Count Good Nodes in Binary Tree Leetcode Solution160
637Isomorphic Strings160
638Minimum Number of Steps to Make Two Strings Anagram Leetcode Solutions160
639Find Maximum Level sum in Binary Tree160
640Valid Palindrome II Leetcode Solution160
641Longest Increasing Subsequence160
642Maximum Consecutive Numbers Present in an Array160
643Iterative Method to find Height of Binary Tree160
644Sum of All Odd Length Subarrays Leetcode Solution160
645Binary Tree Zigzag Level Order Traversal LeetCode Solution160
646Power of Four Leetcode Solution160
647Optimal Account Balancing LeetCode Solution160
648Longest Substring with At Most K Distinct Characters LeetCode Solution160
649GCD Of Two Numbers159
650K Empty Slots159
651Reverse a stack without using extra space in O(n)159
652Merge Two Balanced Binary Search Trees159
653Delete consecutive same words in a sequence159
654Best Time to Buy and Sell Stock with Cooldown Leetcode Solution159
655Check If It Is a Straight Line Leetcode Solution159
656Non-overlapping sum of two sets159
657String to Integer (atoi) LeetCode Solution158
658Queries for counts of array elements with values in given range158
659Maximum Number of Coins You Can Get Leetcode Solution158
660Moving Average from Data Stream Leetcode Solution158
661Number of Provinces Leetcode Solution158
662Convert an array to reduced form158
663Ugly Number Leetcode Solution158
664Check If Two String Arrays are Equivalent Leetcode Solution158
665Strobogrammatic Number LeetCode Solution158
666Letter Combinations of a Phone Number158
667Find the Smallest Divisor given a Threshold Leetcode Solution157
668Print the Fibonacci numbers in reverse order157
669Number of Dice Rolls With Target Sum LeetCode Solution157
670Reducing Dishes LeetCode Solution157
671How to Create Mergable Stack?157
672Longest Substring with At Least K Repeating Characters LeetCode Solution157
673Lucky Numbers in a Matrix Leetcode Solution157
674Reorganize String157
675Employee Free Time LeetCode Solution157
676Find Largest d in Array such that a + b + c = d157
677Flipping an Image LeetCode Solution157
678Wiggle Sort157
679Reverse Only Letters LeetCode Solution157
680Largest Sum Contiguous Subarray157
681Partition Labels LeetCode Solution157
682Increasing Decreasing String Leetcode Solution157
683Longest Increasing Path in a Matrix LeetCode Solution157
684Subset Sum Leetcode157
685Maximum Number of Occurrences of a Substring Leetcode Solution156
686Find the Distance Value Between Two Arrays Leetcode Solution156
687Path With Maximum Minimum Value LeetCode Solution156
688Check if a queue can be sorted into another queue using a stack156
689Form minimum number from given sequence156
690Inorder Successor of a node in Binary Tree156
691Sum of f(a[i], a[j]) over all pairs in an array of n integers156
692Find Leaves of Binary Tree LeetCode Solution156
693Valid Palindrome156
694Find whether an array is subset of another array156
695Unique Paths II Leetcode Solution155
696Reversing a Queue using Recursion155
697Valid Perfect Square Leetcode Solution155
698Permutation Sequence LeetCode Solution155
699Delete Nth node from the end of the given linked list155
700To Lower Case Leetcode Solution155
701Populating Next Right Pointers in Each Node155
702BFS vs DFS for Binary Tree155
703Reservoir Sampling155
704Recover Binary Search Tree155
705Rank Transform of an Array Leetcode Solution154
706Binary Tree zigzag level order Traversal154
707Add and Search Word – Data structure design LeetCode154
708Majority Element II Leetcode Solution154
709Sort Array by Increasing Frequency Leetcode Solution154
710Merge Two Binary Trees LeetCode Solution154
711Hamming Distance Leetcode Solution154
712Edit Distance LeetCode Solution154
713Find pairs with given sum such that elements of pair are in different rows154
714Dynamic Programming Basics154
715Construct BST from given Preorder Traversal154
716Robot Room Cleaner Leetcode Solution154
717Maximum Product of Three Numbers LeetCode Solution153
718Numbers with prime frequencies greater than or equal to k153
719Keyboard Row Leetcode Solution153
720Remove Invalid Parentheses Leetcode Solution153
721Partition Array Into Three Parts With Equal Sum Leetcode Solution153
722Convert a Number to Hexadecimal Leetcode Solution153
723Decompress Run-Length Encoded List Leetcode Solution153
724Find the node with minimum value in a Binary Search Tree153
725Maximum Product of Two Elements in an Array Leetcode Solution153
726Factorial Trailing Zeroes Leetcode Solution153
727Longest Span with same Sum in two Binary arrays152
728Deletion in a Binary Tree152
729Bulb Switcher LeetCode Solution152
730Stack Permutations (Check if an array is stack permutation of other)152
731String Compression LeetCode Solution152
732Largest subarray with equal number of 0s and 1s151
733Symmetric Tree Leetcode Solution151
734Find unique character in a string151
735Queue based approach for first non-repeating character in a stream151
736Non-decreasing Array LeetCode Solution151
737Race Car LeetCode Solution151
738Find Maximum Depth of Nested Parenthesis in a String151
739Find the largest multiple of 3151
740Sorted Linked List to Balanced BST150
741Minimize Maximum Pair Sum in Array LeetCode Solution150
742Remove Nth Node From End of List Leetcode Solution150
743Bubble sort using two Stacks150
744First Unique Character in a String LeetCode Solution150
745Maximum 69 Number Leetcode Solution150
746Find All Duplicates in an Array LeetCode Solution150
747Minimum Distance Between BST Nodes Leetcode Solution150
748Perform String Shifts Leetcode150
749Minimum Height Trees150
750k-th missing element in increasing sequence which is not present in a given sequence150
751Binomial Coefficient150
752Find Pair with Greatest Product in Array150
753Linked List Cycle150
754Invert Binary Tree LeetCode Solution150
755Binary Tree Maximum Path Sum LeetCode Solution150
756Restore IP Addresses Leetcode Solution150
757Find if Path Exists in Graph Leetcode Solution150
758Word Pattern LeetCode Solution150
759Minimum Cost For Tickets Leetcode Solution150
760Elements to be added so that all elements of a range are present in array149
761Diagonal Traversal of Binary Tree149
762Number of Islands II LeetCode Solution149
763Generate all possible sorted arrays from alternate elements of two given sorted arrays149
764Growable array based stack149
765Search in a Binary Search Tree Leetcode Solution149
766Remove Duplicates from Sorted List LeetCode Solution149
767Count quadruples from four sorted arrays whose sum is equal to a given value x149
768Evaluate Reverse Polish Notation LeetCode Solution149
769Kth ancestor of a node in binary tree149
770Finding K closest element149
771Best Meeting Point LeetCode Solution149
772N-Queens LeetCode Solution149
773Find Median from Data Stream LeetCode Solution149
774Student Attendance Record I Leetcode Solution149
775Merge K Sorted Linked Lists149
776Maximum Length of a Concatenated String with Unique Characters Leetcode Solution149
777Jump Game149
778Morris Traversal149
779Split a String in Balanced Strings Leetcode Solution148
780Remove brackets from an algebraic string containing + and – operators148
781Largest rectangular sub-matrix whose sum is 0148
782Number Complement Leetcode Solution148
783Minimum time required to rot all oranges148
784Snakes and Ladders LeetCode Solution148
785Maximum Difference Between Increasing Elements LeetCode Solution148
786Valid Number148
787Minimum Time Visiting All Points Leetcode Solution148
788Program for Bridge and Torch problem148
789Number of NGEs to the Right147
790Merge Sorted Array LeetCode Solution147
791Transpose Graph147
792Nearest Exit from Entrance in Maze LeetCode Solution147
793Nested List Weight Sum II LeetCode Solution147
794Special Array With X Elements Greater Than or Equal X Leetcode Solution147
795Check for Palindrome after every character replacement Query147
796Minimum number of jumps to reach end147
797Relative Ranks Leetcode Solution147
798Maximum Depth of N-ary Tree Leetcode Solution147
799Get Maximum in Generated Array Leetcode Solution147
800Remove Duplicates from Sorted List II147
801Sort an array according to the order defined by another array147
802Largest Rectangle in Histogram LeetCode Solution147
803Search a 2D Matrix II Leetcode Solution147
804Tiling Problem146
805A Space Optimized DP solution for 0-1 Knapsack Problem146
806Crawler Log Folder Leetcode Solution146
807Friends Pairing Problem146
808Final Prices With a Special Discount in a Shop Leetcode Solution146
809Circular Queue146
810Sort Colors146
811One Edit Distance LeetCode Solution146
812String comparison containing wildcards146
813Minimum Number of Taps to Open to Water a Garden LeetCode Solution146
814Convert BST to Min Heap146
815Base 7 Leetcode Solution146
816Check If Array Pairs Are Divisible by k LeetCode Solution146
817Print a Binary Tree in Vertical Order146
818Partition to K Equal Sum Subsets Leetcode Solution146
819Count items common to both the lists but with different prices146
820Sort Array By Parity II Leetcode Solution146
821Reorder Data in Log Files LeetCode Solution145
822Alien Dictionary LeetCode Solution145
823Subsequence of Size K With the Largest Even Sum LeetCode Solution145
824Check if Two Expressions With Brackets are Same145
825Path with maximum average value145
826Subarray Product Less Than K LeetCode Solution145
827Interval Tree145
828Minimum swaps to make sequences increasing145
829Clone Graph LeetCode Solution145
830Longest Subarray Having Count of 1s One More than Count of 0s144
831Minimum Swaps to Make Strings Equal Leetcode Solution144
832Regular Expression Matching144
833Maximum size subarray sum equals k144
834Course Schedule II – LeetCode144
835Total Numbers With no Repeated Digits in a Range144
836Partition List Leetcode Solution144
837Iterative Preorder Traversal144
838Insert into a Binary Search Tree Leetcode Solution144
839Make Two Arrays Equal by Reversing Sub-arrays Leetcode Solution144
840Level order Traversal in Spiral Form144
841Minimum Jumps to Reach Home LeetCode Solution144
842Sorted Array to Balanced BST144
843Design a Stack With Increment Operation Leetcode Solution144
844Last Stone Weight II LeetCode Solution143
845Permutation Coefficient143
846Brightest Position on Street LeetCode Solution143
847Find the Only Repetitive Element Between 1 to N-1143
848Priority Queue using doubly linked list143
849Top K Frequent Words LeetCode Solution143
850Find all triplets with zero sum143
851Count Distinct Elements in Every Window of Size K143
852Maximum Profit in Job Scheduling Leetcode Solution143
853Guess Number Higher or Lower LeetCode Solution143
854Can Place Flowers LeetCode Solution143
855Subset with sum divisible by m143
856Check if a given array can represent Preorder Traversal of Binary Search Tree143
857Find the subarray with least average143
858Union and Intersection of two Linked Lists143
859Water Bottles Leetcode Solution142
860Valid Parentheses Leetcode Solution142
861Minimum Sum Path in a Triangle142
862Three way partitioning of an array around a given range142
863Check whether a given Binary Tree is Complete or not142
864Find All Possible Recipes from Given Supplies LeetCode Solution142
865Maximum Nesting Depth of the Parentheses Leetcode Solution142
866Given an Array of Pairs Find all Symmetric Pairs in it142
867Brick Wall LeetCode Solution142
868Check if an Array is Stack Sortable141
869Lemonade Change Leetcode Solution141
870Range sum queries without updates141
871Matrix Chain Multiplication141
872Tree Traversal (Preorder, Inorder & Postorder)141
873Count ways to reach the nth stair using step 1, 2 or 3141
874Repeated Substring Pattern LeetCode Solution141
875Sum of nearest smaller and greater number141
876Design Browser History LeetCode Solution141
877Binary Search Tree Search and Insertion141
878Least Number of Unique Integers after K Removals Leetcode Solution141
879Form Minimum Number From Given Sequence141
880LCS (Longest Common Subsequence) of three strings141
881Rearrange Spaces Between Words Leetcode Solution141
883Spiral Matrix II Leetcode Solution141
884Count Negative Numbers in a Sorted Matrix LeetCode Solution140
885Find all permuted rows of a given row in a matrix140
886An Interesting Method to generate Binary Numbers from 1 to n140
887Maximum Score After Splitting a String Leetcode Solution140
888Shortest Word Distance Leetcode Solution140
889Insert Delete GetRandom140
890Construct Complete Binary Tree from its Linked List Representation140
891Distinct adjacent elements in an array140
892Count Subarrays with Same Even and Odd Elements140
893GCDs of given index ranges in an array140
894Guess Number Higher or Lower II140
895Best Time to Buy and Sell Stock with Transaction Fee Leetcode Solution140
896Daily Temperatures Leetcode Solution140
897Delete And Earn140
898Destination City Leetcode Solution140
899Robot Bounded In Circle LeetCode Solution139
900Missing Element in Sorted Array LeetCode Solution139
901Diagonal Traversal LeetCode Solution139
902Queries for GCD of all numbers of an array except elements in a given range139
903Find Maximum Sum Possible Equal Sum of Three Stacks139
904Number of Days Between Two Dates LeetCode Solution139
905Check if stack elements are pairwise consecutive139
906Rearrange an Array Such that arr[i] is equal to i139
907Identify and Mark Unmatched Parenthesis in an Expression139
908A program to check if a binary tree is BST or not139
909Sequences of given length where every element is more than or equal to twice of previous139
910Convert Sorted List to Binary Search Tree139
911Set Matrix Zeroes Leetcode Solution139
912Minimum sum of multiplications of n numbers138
913Range LCM Queries138
914Time Based Key-Value Store LeetCode Solution138
915Diagonal Traverse LeetCode Solution138
916Find Common Characters Leetcode Solution138
917Vertical sum in a given binary tree138
918Alien Dictionary138
919Find distance between two nodes of a Binary Tree138
920Check if the given array can represent Level Order Traversal of Binary Search Tree138
921BFS for Disconnected Graph138
922Balanced Expression with Replacement138
923Special Positions in a Binary Matrix Leetcode Solution138
924Merge Two Sorted Lists Leetcode137
925Stone Game II Leetcode137
926Remove Duplicates from Sorted List II LeetCode Solution137
927Number of Distinct Islands Leetcode Solution137
928Palindrome Partitioning Leetcode Solution137
929Spiral Matrix III LeetCode Solution137
930Merging Intervals137
931Longest Palindromic Subsequence137
932Rearrange Array such that arr[i] >= arr[j] if i is even and arr[i] <= arr[j] if i is odd and j < i137
933Queue using Stacks136
934Averages of Levels in Binary Tree136
935Number of Equivalent Domino Pairs Leetcode Solution136
936Can Make Arithmetic Progression From Sequence Leetcode Solution136
937Infix to Postfix136
938Print Fibonacci sequence using 2 variables136
939Maximum Subarray Sum Excluding Certain Elements136
940K’th Largest Element in BST when modification to BST is not allowed136
941Analyze User Website Visit Pattern LeetCode Solution136
942Sliding Window Maximum136
943Maximum Frequency Stack Leetcode Solution136
944Lexicographical Numbers Leetcode Solution136
945Maximize Sum of Array after K Negations Leetcode Solution135
946Construct BST from its given Level Order Traversal135
947Trim a Binary Search Tree135
948Difference Array | Range update query in O(1)135
949Dividing Array into Pairs With Sum Divisible by K135
950Binary Tree Longest Consecutive Sequence LeetCode Solution135
9513 Sum135
952Median of Two Sorted Arrays135
953Binary array after M range toggle operations135
954Construct the Rectangle Leetcode Solution135
955Pattern Occurrences using Stack135
956Three Consecutive Odds Leetcode Solution135
957Largest area rectangular sub-matrix with equal number of 1’s and 0’s135
958Largest Substring Between Two Equal Characters Leetcode Solution134
959Check If a Word Occurs As a Prefix of Any Word in a Sentence Leetcode Solution134
960Height of a generic tree from parent array134
961All Unique Triplets that Sum up to a Given Value134
962Intersection of Two Linked Lists LeetCode Solution134
963Largest divisible pairs subset134
964Check if any two intervals overlap among a given set of intervals134
965Strongly Connected Component134
966Minimum Height Trees LeetCode Solution134
967Word Break134
968Find postorder traversal of BST from preorder traversal134
969Newman-Conway Sequence134
970Find Maximum of Minimum for Every Window Size in a Given Array133
971First missing positive133
972Maximum Product Subarray133
973Breadth First Search (BFS) for a Graph133
974Count Submatrices With All Ones LeetCode Solution133
975Binary Search Tree Delete Operation133
976Create Maximum Number133
977Palindrome Partitioning133
978Shuffle 2n integers as without using extra space133
979Iterative Postorder Traversal Using Two Stacks133
980Depth First Search (DFS) for a Graph133
981Segment Tree133
982Product of Array Except Self LeetCode Solution133
983Symmetric Tree133
984Split Array Into Consecutive Subsequences133
985Kth Smallest Element in a BST Leetcode Solution133
986Reverse Nodes in K-Group133
987Find Duplicate Subtrees132
988The Maze III LeetCode Solution132
989Maximum subsequence sum such that no three are consecutive132
990My Calendar I LeetCode Solution132
991Count Primes in Ranges132
992Length of Longest Fibonacci Subsequence132
993Level Order Traversal of Binary Tree132
994Minesweeper LeetCode Solution132
995Asteroid Collision LeetCode Solution132
996Sign of the Product of an Array LeetCode Solution132
997Rearrange array such that even positioned are greater than odd132
998Climbing stairs132
999Boundary Traversal of binary tree131
1000Double the first element and move zero to end131
1001Partition Equal Subset Sum131
1002Longest Nice Substring LeetCode Solution131
1003Maximum Number of Ways to Partition an Array LeetCode Solution131
1004Kill Process LeetCode Solution131
1005Count pair with Given Sum131
1006Longest subsequence such that difference between adjacents is one131
1007Find the First Circular Tour that visits all the Petrol Pumps131
1008Make The String Great Leetcode Solution131
1009Find the Difference Leetcode Solution131
1010Serialize and Deserialize Binary Tree130
1011Insertion in a Binary Tree130
1012Largest Number Leetcode Solution130
1013Find number of pairs in an array such that their XOR is 0130
1014The Painter’s Partition Problem130
1015Decrypt String from Alphabet to Integer Mapping Leetcode Solution130
1016Super Ugly Number130
1017Graph Valid Tree LeetCode Solution130
1018Level order traversal using two Queues130
1019Shortest Completing Word Leetcode Solution130
1020Unique Paths II130
1021Maximum Length of Repeated Subarray130
1022Number Of Longest Increasing Subsequence129
1023Binary Search Tree129
1024Advantages of BST over Hash Table129
1025Ugly Number II LeetCode Solution129
1026Compute nCr % p129
1027Collect maximum points in a grid using two traversals129
1028K Closest Points to Origin Leetcode Solution129
1029Friends Of Appropriate Ages LeetCode Solution129
1030Design Hit Counter LeetCode Solution129
1031Count subarrays where second highest lie before highest129
1032Valid Boomerang Leetcode Solution129
1033Number of palindromic paths in a matrix128
1034Balanced Binary Tree128
1035Construct Binary Tree from given Parent Array representation128
1036Rearrange an array such that ‘arr[j]’ becomes ‘i’ if ‘arr[i]’ is ‘j’128
1037Scramble String LeetCode Solution128
1038Employee Importance LeetCode Solution128
1039Boolean Parenthesization Problem128
1040Maximum Product of Indexes of Next Greater on Left and Right128
1041Minimum Size Subarray Sum128
1042String Matching in an Array Leetcode Solution128
1043Ugly Numbers128
1044Build an Array With Stack Operations Leetcode Solution128
1045Construction of Longest Increasing Subsequence (N log N)128
1046Available Captures for Rook Leetcode Solution128
1047Next Greater Element III LeetCode Solution128
1048Defanging an IP Address LeetCode Solution128
1049Invalid Transactions LeetCode Solution128
1050Populating Next Right Pointers in Each Node Leetcode Solution127
1051Find Peak Element127
1052Morris Inorder Traversal127
1053Find whether a subarray is in form of a mountain or not127
1054Minimum Index Sum of Two Lists127
1055Maximum Sum of 3 Non-Overlapping Subarrays127
1056Add two numbers127
1057Regular Expression Matching Regular Expression Matching LeetCode Solution127
1058Maximum weight transformation of a given string127
1059Count minimum steps to get the given desired array127
1060Longest Bitonic Subsequence127
1061Maximum difference between frequency of two elements such that element having greater frequency is also greater127
1062Maximum length subsequence with difference between adjacent elements as either 0 or 1127
1063Kth Smallest Element in a Sorted Matrix LeetCode Solution127
1064Recover Binary Search Tree Leetcode Solution126
1065Find the minimum distance between two numbers126
1066Find a Peak Element II LeetCode Solution126
1067Implement Trie (Prefix Tree) Leetcode Solution126
1068Move all negative elements to end in order with extra space allowed126
1069Custom Sort String Leetcode Solution126
1070Bitwise AND of Numbers Range LeetCode Solution126
1071Validate Binary Search Tree126
1072Iterative Depth First Traversal of Graph126
1073Lowest Common Ancestor126
1074Divisible Pairs Counting125
1075Remove Duplicates from Sorted Array II Leetcode Solution125
1076Maximize Distance to Closest Person LeetCode Solution125
1077Determine Whether Matrix Can Be Obtained By Rotation LeetCode Solution125
1078Binary Tree Right Side View LeetCode Solution125
1079Number of Closed Islands Leetcode Solution125
1080Combination Sum IV LeetCode Solution125
1081Smallest Common Region Leetcode Solution125
1082Path Sum II LeetCode Solution125
1083Binary Tree Data Structure125
1084Search in Sorted Rotated Array125
1085Largest BST Subtree LeetCode Solution125
1086Day of the Year Leetcode Solution125
1087Next Permutation Leetcode Solution124
1088Rearrange array such that even index elements are smaller and odd index elements are greater124
1089Remove Palindromic Subsequences Leetcode Solution124
1090Number of Students Doing Homework at a Given Time Leetcode Solution124
1091Clone a Binary Tree with Random Pointers124
1092Increasing Triplet Subsequence LeetCode Solution124
1093Path Sum124
1094Subarrays with K Different Integers Leetcode Solution124
1095Types of Binary Tree124
1096Print all triplets in sorted array that form AP123
1097Number of siblings of a given Node in n-ary Tree123
1098Find Smallest Range Containing Elements from k Lists123
1099Level of Each node in a Tree from source node123
1100Topological Sorting123
1101Serialize and Deserialize Binary Tree LeetCode Solution123
1102Consecutive Characters LeetCode Solution123
1103Generate Parentheses Leetcode Solution123
1104Count pairs from two sorted arrays whose sum is equal to a given value x123
1105Print Next Greater Number of Q queries123
1106Kth Smallest Product of Two Sorted Arrays LeetCode Solution123
1107Maximum Product Subarray122
1108Find maximum difference between nearest left and right smaller elements122
1109Bottom View of a Binary Tree122
1110Distinct Subsequences122
1111Remove duplicates from sorted array122
1112Root to Leaf path with target sum Leetcode Solutions122
1113Maximum Binary Tree121
1114Count Largest Group Leetcode Solution121
1115Minimum Score Triangulation of Polygon Leetcode Solution121
1116Valid Tic-Tac-Toe State LeetCode Solution121
1117Constant time range add operation on an array121
1118Write Code to Determine if Two Trees are Identical121
1119Third Maximum Number Leetcode Solution121
1120Convert BST into a Min-Heap without using array121
1121Find Three Element From Different Three Arrays Such That a + b + c = sum121
1122Construct Binary Tree from Preorder and Postorder Traversal LeetCode Solution121
1123Print Right View of a Binary Tree121
1124Cutting a Rod121
1125Longest Subarray of 1’s After Deleting One Element LeetCode Solution120
1126Products of ranges in an array120
1127Cells with Odd Values in a Matrix LeetCode Solution120
1128Search Insert Position120
1129Queries for Number of Distinct Elements in a Subarray120
1130Iterative method to find ancestors of a given binary tree120
1131Reformat The String Leetcode Solution120
1132Search an Element in Sorted Rotated Array120
1133Minimum sum of squares of character counts in a given string after removing k characters120
1134Golomb sequence120
1135Mean of Array After Removing Some Elements Leetcode Solution120
1136Palindrome Permutation LeetCode Solution120
1137Prime Palindrome LeetCode Solution119
1138Construct K Palindrome Strings LeetCode Solution119
1139Moser-de Bruijn Sequence119
1140Longest Increasing Consecutive Subsequence119
1141Red-Black Tree Introduction119
1142Print modified array after executing the commands of addition and subtraction119
1143Minimum Absolute Difference in BST Leetcode Solution119
1144Thousand Separator Leetcode Solution119
1145Find a sorted subsequence of size 3 in linear time118
1146Find maximum length Snake sequence118
1147Delete Nodes and Return Forest Leetcode Solution118
1148Binary Tree to Binary Search Tree Conversion118
1149Sum of Even Numbers After Queries118
1150Swap Nodes In Pairs117
1151Factorial Trailing Zeroes LeetCode Solution117
1152Decision Tree117
1153Count even length binary sequences with same sum of first and second half bits117
1154K maximum sums of overlapping contiguous sub-arrays117
1155Merge two BSTs with limited extra space117
1156Check Array Formation Through Concatenation Leetcode Solution117
1157Transform a BST to Greater sum Tree117
1158Possible Bipartition LeetCode Solution117
1159Kth Smallest Number in Multiplication Table Leetcode Solution117
1160Maximum Product of Splitted Binary Tree LeetCode Solution117
1161Palindromic Substrings Leetcode Solution117
1162Find Two Non-overlapping Sub-arrays Each With Target Sum LeetCode Solution117
1163Longest Repeated Subsequence117
1164Find the smallest binary digit multiple of given number117
1165Priority Queue116
1166Rotate Array116
1167K’th Largest element in BST using constant extra space116
1168Compare Strings by Frequency of the Smallest Character Leetcode Solution116
1169Swapping Nodes in a Linked List Leetcode Solution116
1170Number of Orders in the Backlog Leetcode Solution116
1171Maximize sum of consecutive differences in a circular array116
1172Minimum Cost to Move Chips to The Same Position LeetCode Solution116
1173Minimum Sideway Jumps LeetCode Solution116
1174Subset Sum Problem in O(sum) space116
1175Bus Routes Leetcode Solution116
1176Web Crawler LeetCode Solution116
1177First Bad Version115
1178Find Largest Value in Each Tree Row LeetCode Solution115
1179Search Suggestions System LeetCode Solution115
1180Closest Binary Search Tree Value Leetcode Solution115
1181Minimum Moves to Equal Array Elements LeetCode Solution115
1182Count Pairs Whose Products Exist in Array114
1183Given a binary tree, how do you remove all the half nodes?114
1184Diameter of N-Ary Tree LeetCode Solution114
1185Remove Max Number of Edges to Keep Graph Fully Traversable Leetcode Solution114
1186Closest Leaf in a Binary Tree LeetCode Solution114
1187Decrease Elements To Make Array Zigzag LeetCode Solution114
1188Convert Sorted Array to Binary Search Tree LeetCode Solutions113
1189Queue Reconstruction by Height113
1190Matchsticks to Square Leetcode Solution113
1191Maximum number of segments of lengths a, b and c113
1192Moving Stones Until Consecutive Leetcode Solution113
1193Contiguous Array LeetCode Solution113
1194Reverse a Path in BST using Queue113
1195Array Queries for multiply replacements and product112
1196Filter Restaurants by Vegan-Friendly, Price and Distance Leetcode Solution112
1197Reformat Date LeetCode Solution112
1198Valid Triangle Number112
1199Champagne Tower LeetCode Solution112
1200Maximum sum bitonic subarray112
1201Write a function to get the intersection point of two Linked Lists112
1202Lowest Common Ancestor in Binary Search Tree112
1203Maximum Depth Of Binary Tree112
1204Kth Smallest Element in a BST112
1205Sum of Left Leaves LeetCode Solution111
1206Range Sum Query using Sparse Table111
1207Maximum sum of pairs with specific difference111
1208New 21 Game111
1209Replace two consecutive equal values with one greater111
1210How to print maximum number of A’s using given four keys111
1211Divide Two Integers Leetcode Solution110
1212Range Queries for Longest Correct Bracket Subsequence110
1213Integer Break LeetCode Solution110
1214Graph and its representation110
1215Valid Perfect Square LeetCode Solution110
1216Concatenation of Array LeetCode Solution110
1217Guess The Word110
1218Maximum Value at a Given Index in a Bounded Array LeetCode Solution110
1219Design Skiplist LeetCode Solution110
1220Convert Integer to the Sum of Two No-Zero Integers Leetcode Solution110
1221Symmetric Tree LeetCode Solution Leetcode Solution109
1222The kth Factor of n Leetcode Solution109
1223Check if each internal node of a BST has exactly one child109
1224Path Crossing Leetcode Solution109
1225BST to a Tree with Sum of all Smaller Keys109
1226Merge Sort109
1227Check for Identical BSTs without building the trees109
1228Maximum sum of a path in a Right Number Triangle109
1229Print modified array after multiple array range increment operations109
1230Lowest Common Ancestor of a Binary Tree Leetcode Solution109
1231Flatten 2D Vector LeetCode Solution109
1232Check Completeness of a Binary Tree LeetCode Solution109
1233Perfect Squares LeetCode Solution109
1234Arithmetic Slices II – Subsequence LeetCode Solution109
1235Sliding Window Median Leetcode Solution108
1236Queries on Probability of Even or Odd Number in given Ranges108
1237Minimum Swaps To Make Sequences Increasing LeetCode Solution108
1238Longest Common Prefix Using Word by Word Matching108
1239Parallel Courses II LeetCode Solution108
1240Check if all levels of two Binary Tree are anagrams or not108
1241Count Subsets Having Distinct Even Numbers108
1242Largest Plus Sign Leetcode Solution107
1243Count and Toggle Queries on a Binary Array107
1244Contiguous Array107
1245Power of Two107
1246Maximize Elements Using Another Array107
1247Maximum Array from Two given Arrays Keeping Order Same107
1248Mean of range in array107
1249Find Minimum in Rotated Sorted Array II LeetCode Solution107
1250Graph Cloning107
1251LRU Cache Leetcode Solution106
1252Check If a String Can Break Another String Leetcode Solution106
1253Print n terms of Newman-Conway Sequence106
1254Bold Words in String LeetCode Solution106
1255Find minimum number of merge operations to make an array palindrome106
1256Missing Number106
1257Excel Sheet Column Title LeetCode Solution105
1258Image Overlap LeetCode Solution105
1259Find k-th smallest element in BST (Order Statistics in BST)105
1260Minimum Remove to Make Valid Parentheses LeetCode Solution105
1261Verify Preorder Serialization of a Binary Tree105
1262Merge k Sorted Lists Leetcode Solution104
1263Print Ancestors of a Given Binary Tree Node Without Recursion104
1264Next greater element104
1265Maximum Product Subarray104
1266Minimum Time to Collect All Apples in a Tree LeetCode Solution103
1267Smallest Range II Leetcode Solution103
1268Palindrome Partitioning103
1269Check if two nodes are on the same path in a Tree102
1270Min Cost Climbing Stairs LeetCode Solution102
1271Orderly Queue LeetCode Solution101
1272Merge Sorted Array101
1273Check in binary array the number represented by a subarray is odd or even101
1274Koko Eating Bananas LeetCode Solution100
1275Newman–Shanks–Williams prime99
1276Number of elements less than or equal to a given number in a given subarray99
1277Peeking Iterator LeetCode Solution99
1278Check if X can give change to every person in the Queue99
1279Different Ways to Add Parentheses Leetcode Solution99
1280Find maximum average subarray of k length97
1281Range Minimum Query (Square Root Decomposition and Sparse Table)97
1282Maximum Sum Increasing Subsequence97
1283Largest Submatrix With Rearrangements LeetCode Solution97
1284Number of indexes with equal elements in given range96
1285Queries for Decimal Values of Subarrays of a Binary Array96
1286Longest Substring Without Repeating Characters Leetcode Solution95
1287Minimum Total Space Wasted With K Resizing Operations LeetCode Solution95
1288Array Nesting Leetcode Solution95
1289Maximum product of an increasing subsequence95
1290Check given array of size n can represent BST of n levels or not94
1291Arranging Coins Leetcode Solution93
1292Binary Tree to Binary Search Tree Conversion using STL set93
1293Encoded String With Shortest Length LeetCode Solution92
1294Random Pick Index LeetCode Solution92
1295Reach a Number LeetCode Solution92
1296Convert to Base -2 LeetCode Solution92
1297Minimum Number of People to Teach LeetCode Solution92
1298Jump Game IV LeetCode Solution92
1299Queries on XOR of greatest odd divisor of the range91
1300Convert a BST to a Binary Tree such that sum of all greater keys is added to every key91
1301Find the Winner of the Circular Game LeetCode Solution91
1302Minimum Possible Integer After at Most K Adjacent Swaps On Digits LeetCode Solution90
1303Insert Delete GetRandom O(1) Leetcode Solution90
1304Number of Subsequences That Satisfy the Given Sum Condition LeetCode solution88
1305Palindrome Number LeetCode Solution88
1306Add Two Numbers II Leetcode Solution87
1307Vertical Order Traversal of Binary Tree LeetCode Solution87
1308Design Underground System Leetcode Solution85
1309Print Maximum Length Chain of Pairs84
1310Continuous Subarray Sum LeetCode Solution83
1311Detect Capital Leetcode Solution81
1312Design A Leaderboard Leetcode Solution79
1313Minimum Swaps to Group All 1’s Together Leetcode Solution77
1314Substring with Concatenation of All Words Leetcode Solution77
1315Top K Frequent Elements LeetCode Solution77
1316Minimum Path Sum Leetcode Solution73
1317Decode String Leetcode Solution73
1318Count Sub Islands LeetCode Solution72
1319Odd Even Linked List Leetcode Solution72
1320Binary Tree Inorder Traversal LeetCode Solution72
1321Shifting Letters LeetCode Solution71
1322Shortest Unsorted Continuous Subarray LeetCode Solution71
1323Find the Town Judge LeetCode Solution70
1324Maximum Population Year LeetCode Solution70
1325Sum Root to Leaf Numbers LeetCode Solution70
1326Best Meeting Point LeetCode Solution69
1327Find the Town Judge LeetCode Solution68
1328Longest Common Subsequence LeetCode Solution68
1329Design Add and Search Words Data Structure LeetCode Solution66
1330Score of Parenthesis LeetCode Solution64
1331Rectangle Overlap LeetCode Solution64
1332Maximum Population Year LeetCode Solution64
1333Stone Game IV LeetCode Solution62
1334Insert into a Sorted Circular Linked List LeetCode Solution62
1335Flatten Binary Tree to Linked List LeetCode Solution61
1336Range Sum Query 2D – Immutable LeetCode Solution60
1337Valid Triangle Number LeetCode Solution59
1338Is Graph Bipartite? LeetCode Solution57
1339Reveal Cards In Increasing Order Leetcode Solution54
1340Divide Chocolate LeetCode Solution50
1341Step-By-Step Directions From a Binary Tree Node to Another LeetCode Solution42
1342Range Sum of BST LeetCode Solution42
1343Reverse Integer Leetcode Solution39
1344Sort Colors LeetCode Solution37
1345Find K Closest Elements LeetCode Solution34
1346Excel Sheet Column Number LeetCode Solution33
1347Rotate String LeetCode Solution32
1348Maximum Side Length of a Square with Sum Less than or Equal to Threshold LeetCode Solution30
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