Insert Delete GetRandom O(1) - Duplicates allowed LeetCode Solution

Table of Contents

Problem Statement:

Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution: RandomizedCollection is a data structure that contains a collection of numbers, possibly duplicates (i.e., a multiset). It should support inserting and removing specific elements and also removing a random element.

Implement the RandomizedCollection class:

RandomizedCollection() Initializes the empty RandomizedCollection object.
bool insert(int val) Inserts an item val into the multiset, even if the item is already present. Returns true if the item is not present, false otherwise.
bool remove(int val) Removes an item val from the multiset if present. Returns true if the item is present, false otherwise. Note that if val has multiple occurrences in the multiset, we only remove one of them.
int getRandom() Returns a random element from the current multiset of elements. The probability of each element being returned is linearly related to the number of same values the multiset contains.

You must implement the functions of the class such that each function works on average O(1) time complexity.

Note: The test cases are generated such that getRandom will only be called if there is at least one item in the RandomizedCollection.

Examples:

Input

["RandomizedCollection", "insert", "insert", "insert", "getRandom", "remove", "getRandom"]
[[], [1], [1], [2], [], [1], []]

Output

[null, true, false, true, 2, true, 1]

Explanation

RandomizedCollection randomizedCollection = new RandomizedCollection();
randomizedCollection.insert(1);   // return true since the collection does not contain 1.
                                  // Inserts 1 into the collection.
randomizedCollection.insert(1);   // return false since the collection contains 1.
                                  // Inserts another 1 into the collection. Collection now contains [1,1].
randomizedCollection.insert(2);   // return true since the collection does not contain 2.
                                  // Inserts 2 into the collection. Collection now contains [1,1,2].
randomizedCollection.getRandom(); // getRandom should:
                                  // - return 1 with probability 2/3, or
                                  // - return 2 with probability 1/3.
randomizedCollection.remove(1);   // return true since the collection contains 1.
                                  // Removes 1 from the collection. Collection now contains [1,2].
randomizedCollection.getRandom(); // getRandom should return 1 or 2, both equally likely.

Approach:

Idea:

The data structure can be implemented with the help of a Hash_map consisting of a pair of <int, Hash_set> and an arrayList. The Hash_map will store the indices of the elements and the list will store the list of elements present so far. The required methods can be implemented as follows:

insert: Insert the element to the list and add the index to HashMap[element].
remove: First, we find any index of the element to be removed in the HashMap. Now we will update the element in this index with the last element of the list. Since the last element of the list has been assigned a new index, we have to update its value in the HashMap. We also have to get rid of the index of the element we removed from the HashMap.
getRandom: Just sample a random element from the list.

Code for Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution:

C++ Solution:

class RandomizedCollection {
public:
    unordered_map<int,unordered_set<int>> mp;
    vector<int> arr;
    int size = 0;
    
    RandomizedCollection() {
        
    }
    
    bool insert(int val) {
        bool status = not mp.count(val);
        mp[val].insert(size);
        arr.push_back(val);
        size++;
        return status;
    }
    
    bool remove(int val) {
        bool status = mp.count(val);
        if(status){
            int last_element = arr.back();
            if(val == last_element){
                mp[val].erase(arr.size()-1);
                arr.pop_back();
                size--;
                if(mp[val].size()==0)
                    mp.erase(val);
            }
            else{
                int index;
                for(auto it:mp[val]){
                    index = it;
                    break;
                }
                arr[index] = last_element;
                mp[last_element].erase(arr.size()-1);
                arr.pop_back();
                size--;
                mp[val].erase(index);
                mp[last_element].insert(index);
                if(mp[val].size()==0)
                    mp.erase(val);
            } 
        }
        return status;
    }
    
    int getRandom() {
        return arr[rand()%arr.size()];
    }
};

/**
 * Your RandomizedCollection object will be instantiated and called as such:
 * RandomizedCollection* obj = new RandomizedCollection();
 * bool param_1 = obj->insert(val);
 * bool param_2 = obj->remove(val);
 * int param_3 = obj->getRandom();
 */

Complexity Analysis of Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution:

Time Complexity: The time complexity of the above code is O(n) with n being the number of operations.
Space Complexity: The space complexity of the above code is O(n).

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469	Balanced Binary Tree Leetcode Solution	189
470	Longest Common Subsequence	189
471	Find all pairs (a, b) in an array such that a % b = k	189
472	Edit Distance	188
473	Concatenation of Array LeetCode Solution	188
474	Fizz Buzz	188
475	Count pairs from two linked lists whose sum is equal to a given value	188
476	Find the Difference Leetcode Solution	188
477	Minimum Moves to Equal Array Elements Leetcode Solution	188
478	Kids With the Greatest Number of Candies Leetcode Solution	188
479	The K Weakest Rows in a Matrix Leetcode Solution	187
480	Kth Largest Element in a Stream Leetcode Solution	187
481	Floyd Warshall Algorithm	187
482	Remove Minimum Number of Elements Such That no Common Element Exist in both Array	187
483	Find First and Last Position of Element in Sorted Array Leetcode Solution	187
484	Word Ladder LeetCode Solution	187
485	Find elements which are present in first array and not in second	187
486	Degree of an array	186
487	Longest Common Prefix using Trie	186
488	Find subarray with given sum (Handles Negative Numbers)	186
489	Text Justification LeetCode Solution	186
490	Count and Say	186
491	Next Greater Element I Leetcode Solution	186
492	Design Parking System Leetcode Solution	186
493	Number of Steps to Reduce a Number to Zero Leetcode Solution	186
494	Merge Overlapping Intervals	185
495	MiniMax Algorithm	185
496	Multiply Strings Leetcode Solution	185
497	Prefix to Postfix Conversion	185
498	Flood Fill LeetCode	185
499	Zigzag Conversion LeetCode Solution	185
500	Count and Say Leetcode Solution	185
501	Reverse a linked list	184
502	Shortest Palindrome	184
503	Top View of Binary Tree	183
504	Slowest Key Leetcode Solution	183
505	Max Area of Island	183
506	Pair with given product	183
507	Convert array into Zig-Zag fashion	183
508	Length of Last Word Leetcode Solution	183
509	Find four elements that sum to a given value (Hashmap)	183
510	The Stock Span Problem	183
511	Substring With Concatenation Of All Words	183
512	Mobile Numeric Keypad Problem	183
513	Recursion	183
514	Longest subarray not having more than K distinct elements	183
515	Priority Queue in C++	183
516	Jump Game Leetcode Solution	183
517	Move Zeroes LeetCode Solution	183
518	Valid Parenthesis String	183
519	Peak Index in a Mountain Array	183
520	Find N Unique Integers Sum up to Zero Leetcode Solution	183
521	Next Greater Frequency Element	183
522	Iterative Inorder Traversal of a Binary Tree	182
523	Shuffle String Leetcode Solution	182
524	Find distinct elements common to all rows of a matrix	182
525	Check if a given array contains duplicate elements within k distance from each other	182
526	Implement a stack using single queue	182
527	Longest Common Prefix using Sorting	182
528	Intersection of Two Arrays	182
529	Find any one of the multiple repeating elements in read only array	181
530	Find missing elements of a range	181
531	Postfix to Prefix Conversion	181
532	Last Stone Weight	181
533	Find Index of Closing Bracket for a Given Opening Bracket in an Expression	181
534	Count number of triplets with product equal to given number	181
535	Contiguous Array Leetcode	180
536	Relative Sort Array Leetcode Solution	180
537	Koko Eating Bananas Leetcode Solution	180
538	Delete Node in a Linked List Leetcode Solution	180
539	Smallest Subarray With all Occurrences of a Most Frequent Element	179
540	Implement Stack using Queues	179
541	Excel Sheet Column Title Leetcode Solution	179
542	N-th Tribonacci Number Leetcode Solution	179
543	Convert a normal BST to Balanced BST	179
544	Isomorphic Strings Leetcode Solution	178
545	Change the Array into Permutation of Numbers From 1 to N	178
546	Linked List Cycle II LeetCode Solution	178
547	Best Time to Buy and Sell Stock	178
548	Container with Most Water	178
549	Convert Sorted Array to Binary Search Tree Leetcode Solution	177
550	First negative integer in every window of size k	177
551	Assign Cookies Leetcode Solution	177
552	Minimum Operations to convert X to Y	177
553	Rearrange a binary string as alternate x and y occurrences	177
554	Build Array From Permutation Leetcode Solution	177
555	Implementation of Deque using circular array	177
556	Check for Balanced Parentheses in an Expression	177
557	Find Words That Can Be Formed by Characters Leetcode Solution	177
558	Largest Perimeter Triangle Leetcode Solution	177
559	Jewels and Stones Leetcode Solution	177
560	Valid Anagrams	177
561	Is Subsequence Leetcode Solution	177
562	Minimum Bracket Reversals	177
563	Group Multiple Occurrence of Array Elements Ordered by first Occurrence	177
564	Combinations Leetcode Solution	176
565	K-th Distinct Element in an Array	176
566	Shuffle an Array	176
567	Valid Sudoku	176
568	Hamming Distance	176
569	Sum of Left Leaves Leetcode Solutions	176
570	Arrange given numbers to form the biggest number	176
571	Distribute Candies to People Leetcode Solution	176
572	Island Perimeter Leetcode Solution	176
573	Integer to Roman	176
574	Gold Mine Problem	176
575	Remove Linked List Elements Leetcode Solution	176
576	Rotate List Leetcode Solution	175
577	01 Matrix LeetCode Solution	175
578	Summary Ranges Leetcode Solution	175
579	Unique Binary Search Trees	175
580	Minimum Delete Operations to make all Elements of Array Same	175
581	Largest Sum Contiguous Subarray	175
582	Minimum Knight Moves LeetCode Solution	175
583	LRU Cache LeetCode Solution	174
584	Maximum sum rectangle in a 2D matrix	174
585	Count the number of nodes at given level in a tree using BFS	174
586	Decode Ways	174
587	Count all subsequences having product less than K	174
588	The Knapsack Problem	174
589	Distance Between Bus Stops Leetcode Solution	173
590	Shortest Path in a Grid with Obstacles Elimination LeetCode Solution	173
591	Maximum Number of Chocolates to be Distributed Equally Among k Students	173
592	Find the smallest positive integer value that cannot be represented as sum of any subset of a given array	173
593	Insert Interval Leetcode Solution	173
594	3Sum Closest LeetCode Solution	173
595	Maximum path sum in a triangle	173
596	Minimum number of distinct elements after removing m items	172
597	Trapping Rain Water LeetCode Solution	172
598	Maximum Distance in Array	172
599	Minimum number of subsets with distinct elements	171
600	How to check if two given sets are disjoint?	171
601	Rotate Image LeetCode Solution	171
602	Sort Characters By Frequency LeetCode Solution	171
603	Find minimum difference between any two elements	170
604	Frog Jump Leetcode Solution	170
605	K Empty Slots LeetCode	170
606	Permutation in String Leetcode Solution	170
607	Word Pattern	170
608	Same Tree LeetCode Solution	170
609	Stone Game LeetCode	170
610	Sieve of Eratosthenes	170
611	Sort Array By Parity LeetCode Solution	170
612	Minimum insertions to form a palindrome with permutations allowed	169
613	Applications of Breadth First Search and Depth First Search	169
614	Best Time to Buy and Sell Stock LeetCode Solution	169
615	Painting Fence Algorithm	169
616	Distance of nearest cell having 1 in a binary matrix	169
617	Minimum Depth of Binary Tree Leetcode Solution	169
618	Remove All Occurrences of a Substring LeetCode Solution	169
619	Replace Elements with Greatest Element on Right Side Leetcode Solution	169
620	Find if an Expression has Duplicate Parenthesis or Not	169
621	Printing brackets in Matrix Chain Multiplication Problem	169
622	Isomorphic Strings	169
623	Smallest Good Base	169
624	XOR Operation in an Array Leetcode Solution	169
625	House Robber	168
626	Longest Substring with At Most K Distinct Characters LeetCode Solution	168
627	Minimum Cost to Hire K Workers	168
628	Reverse a stack without using extra space in O(n)	168
629	Segregate 0s and 1s in an Array	168
630	Find Sum of all unique sub-array sum for a given array	168
631	License Key Formatting Leetcode Solution	168
632	Tracking current Maximum Element in a Stack	168
633	Maximum Consecutive Numbers Present in an Array	168
634	Find the Duplicate Number LeetCode Solution	168
635	Word Wrap Problem	168
636	Defanging an IP Address Leetcode Solution	168
637	Binary Tree Zigzag Level Order Traversal LeetCode Solution	167
638	Wiggle Sort	167
639	Iterative Method to find Height of Binary Tree	167
640	Maximum difference between first and last indexes of an element in array	167
641	Count Good Nodes in Binary Tree Leetcode Solution	167
642	Coin Change Problem	167
643	Sum of All Odd Length Subarrays Leetcode Solution	166
644	Optimal Account Balancing LeetCode Solution	166
645	Merge Two Balanced Binary Search Trees	166
646	Find Maximum Level sum in Binary Tree	166
647	Best Time to Buy and Sell Stock with Cooldown Leetcode Solution	166
648	Valid Palindrome II Leetcode Solution	166
649	Queries for counts of array elements with values in given range	166
650	Check If It Is a Straight Line Leetcode Solution	166
651	Minimum Number of Steps to Make Two Strings Anagram Leetcode Solutions	166
652	How to Create Mergable Stack?	166
653	Maximum Number of Occurrences of a Substring Leetcode Solution	166
654	Kth Missing Positive Number Leetcode Solution	166
655	Non-overlapping sum of two sets	166
656	GCD Of Two Numbers	166
657	Valid Palindrome	165
658	Longest Substring with At Least K Repeating Characters LeetCode Solution	165
659	Longest Increasing Subsequence	165
660	Find the Distance Value Between Two Arrays Leetcode Solution	165
661	Moving Average from Data Stream Leetcode Solution	165
662	Convert an array to reduced form	165
663	Flipping an Image LeetCode Solution	165
664	Path With Maximum Minimum Value LeetCode Solution	165
665	Strobogrammatic Number LeetCode Solution	165
666	Employee Free Time LeetCode Solution	165
667	Find Largest d in Array such that a + b + c = d	165
668	Delete consecutive same words in a sequence	164
669	Reorganize String	164
670	Find pairs with given sum such that elements of pair are in different rows	164
671	Maximum Number of Coins You Can Get Leetcode Solution	164
672	Number of Provinces Leetcode Solution	164
673	Partition Labels LeetCode Solution	164
674	Letter Combinations of a Phone Number	164
675	Populating Next Right Pointers in Each Node	163
676	Recover Binary Search Tree	163
677	Power of Four Leetcode Solution	163
678	Edit Distance LeetCode Solution	163
679	Longest Increasing Path in a Matrix LeetCode Solution	163
680	Permutation Sequence LeetCode Solution	163
681	Print the Fibonacci numbers in reverse order	163
682	Valid Perfect Square Leetcode Solution	163
683	Number of Dice Rolls With Target Sum LeetCode Solution	163
684	Reducing Dishes LeetCode Solution	163
685	Rearrange an array in order – smallest, largest, 2nd smallest, 2nd largest	163
686	Check if a queue can be sorted into another queue using a stack	162
687	Partition Array Into Three Parts With Equal Sum Leetcode Solution	162
688	K Empty Slots	162
689	Form minimum number from given sequence	162
690	Lucky Numbers in a Matrix Leetcode Solution	162
691	BFS vs DFS for Binary Tree	162
692	Sort Array by Increasing Frequency Leetcode Solution	162
693	Construct BST from given Preorder Traversal	162
694	Check If Two String Arrays are Equivalent Leetcode Solution	162
695	To Lower Case Leetcode Solution	161
696	Reservoir Sampling	161
697	Inorder Successor of a node in Binary Tree	161
698	Reversing a Queue using Recursion	161
699	Binary Tree zigzag level order Traversal	161
700	Find whether an array is subset of another array	161
701	Merge Two Binary Trees LeetCode Solution	161
702	Dynamic Programming Basics	161
703	Maximum Product of Two Elements in an Array Leetcode Solution	161
704	Ugly Number Leetcode Solution	161
705	Remove Invalid Parentheses Leetcode Solution	161
706	String to Integer (atoi) LeetCode Solution	161
707	Factorial Trailing Zeroes Leetcode Solution	161
708	Robot Room Cleaner Leetcode Solution	161
709	Convert a Number to Hexadecimal Leetcode Solution	161
710	Subset Sum Leetcode	160
711	Majority Element II Leetcode Solution	160
712	Keyboard Row Leetcode Solution	160
713	Binomial Coefficient	160
714	Increasing Decreasing String Leetcode Solution	160
715	Reverse Only Letters LeetCode Solution	160
716	Delete Nth node from the end of the given linked list	160
717	Restore IP Addresses Leetcode Solution	160
718	Find Leaves of Binary Tree LeetCode Solution	160
719	Unique Paths II Leetcode Solution	159
720	Add and Search Word – Data structure design LeetCode	159
721	Decompress Run-Length Encoded List Leetcode Solution	159
722	Find the largest multiple of 3	159
723	Bulb Switcher LeetCode Solution	159
724	Minimum Cost For Tickets Leetcode Solution	158
725	Find the Smallest Divisor given a Threshold Leetcode Solution	158
726	Morris Traversal	158
727	Find the node with minimum value in a Binary Search Tree	158
728	Find Pair with Greatest Product in Array	158
729	Perform String Shifts Leetcode	158
730	Maximum Product of Three Numbers LeetCode Solution	158
731	Finding K closest element	158
732	Maximum 69 Number Leetcode Solution	158
733	First Unique Character in a String LeetCode Solution	157
734	Sum of f(a[i], a[j]) over all pairs in an array of n integers	157
735	Find Maximum Depth of Nested Parenthesis in a String	157
736	Sorted Linked List to Balanced BST	157
737	Number of Islands II LeetCode Solution	157
738	Invert Binary Tree LeetCode Solution	157
739	Minimum Distance Between BST Nodes Leetcode Solution	157
740	Numbers with prime frequencies greater than or equal to k	157
741	Merge K Sorted Linked Lists	157
742	Maximum Depth of N-ary Tree Leetcode Solution	156
743	Find All Duplicates in an Array LeetCode Solution	156
744	Non-decreasing Array LeetCode Solution	156
745	Check If Array Pairs Are Divisible by k LeetCode Solution	156
746	Tiling Problem	156
747	Word Pattern LeetCode Solution	156
748	Hamming Distance Leetcode Solution	156
749	Queue based approach for first non-repeating character in a stream	156
750	Generate all possible sorted arrays from alternate elements of two given sorted arrays	156
751	Find unique character in a string	156
752	Diagonal Traversal of Binary Tree	156
753	Largest subarray with equal number of 0s and 1s	156
754	Special Array With X Elements Greater Than or Equal X Leetcode Solution	156
755	Bubble sort using two Stacks	156
756	Student Attendance Record I Leetcode Solution	156
757	Longest Span with same Sum in two Binary arrays	156
758	Rank Transform of an Array Leetcode Solution	156
759	String Compression LeetCode Solution	156
760	Minimum Height Trees	156
761	Find Median from Data Stream LeetCode Solution	155
762	Largest Rectangle in Histogram LeetCode Solution	155
763	Best Meeting Point LeetCode Solution	155
764	Largest rectangular sub-matrix whose sum is 0	155
765	Minimum time required to rot all oranges	155
766	Search a 2D Matrix II Leetcode Solution	155
767	Jump Game	155
768	Find if Path Exists in Graph Leetcode Solution	155
769	Symmetric Tree Leetcode Solution	155
770	Kth ancestor of a node in binary tree	155
771	Maximum Length of a Concatenated String with Unique Characters Leetcode Solution	155
772	Stack Permutations (Check if an array is stack permutation of other)	155
773	Binary Tree Maximum Path Sum LeetCode Solution	155
774	Elements to be added so that all elements of a range are present in array	155
775	Evaluate Reverse Polish Notation LeetCode Solution	155
776	Final Prices With a Special Discount in a Shop Leetcode Solution	155
777	Split a String in Balanced Strings Leetcode Solution	154
778	Remove Nth Node From End of List Leetcode Solution	154
779	Maximum Difference Between Increasing Elements LeetCode Solution	154
780	Minimize Maximum Pair Sum in Array LeetCode Solution	154
781	k-th missing element in increasing sequence which is not present in a given sequence	154
782	Remove brackets from an algebraic string containing + and – operators	154
783	Program for Bridge and Torch problem	154
784	Snakes and Ladders LeetCode Solution	154
785	Race Car LeetCode Solution	154
786	Transpose Graph	154
787	Count items common to both the lists but with different prices	153
788	Sort an array according to the order defined by another array	153
789	N-Queens LeetCode Solution	153
790	Number of NGEs to the Right	153
791	Last Stone Weight II LeetCode Solution	153
792	Minimum Jumps to Reach Home LeetCode Solution	153
793	Count quadruples from four sorted arrays whose sum is equal to a given value x	153
794	Valid Number	153
795	Partition to K Equal Sum Subsets Leetcode Solution	153
796	Linked List Cycle	153
797	Deletion in a Binary Tree	153
798	Search in a Binary Search Tree Leetcode Solution	153
799	Get Maximum in Generated Array Leetcode Solution	152
800	Check for Palindrome after every character replacement Query	152
801	Number Complement Leetcode Solution	152
802	Minimum swaps to make sequences increasing	152
803	A Space Optimized DP solution for 0-1 Knapsack Problem	152
804	Course Schedule II – LeetCode	152
805	Priority Queue using doubly linked list	152
806	Remove Duplicates from Sorted List LeetCode Solution	152
807	Nearest Exit from Entrance in Maze LeetCode Solution	152
808	Interval Tree	152
809	Print a Binary Tree in Vertical Order	152
810	Remove Duplicates from Sorted List II	152
811	Check if Two Expressions With Brackets are Same	152
812	Reorder Data in Log Files LeetCode Solution	152
813	Minimum Time Visiting All Points Leetcode Solution	152
814	Minimum number of jumps to reach end	152
815	Spiral Matrix II Leetcode Solution	151
816	Maximum size subarray sum equals k	151
817	Find all triplets with zero sum	151
818	Nested List Weight Sum II LeetCode Solution	151
819	One Edit Distance LeetCode Solution	151
820	String comparison containing wildcards	151
821	Iterative Preorder Traversal	151
822	Base 7 Leetcode Solution	151
823	Relative Ranks Leetcode Solution	151
824	Sort Array By Parity II Leetcode Solution	151
825	Crawler Log Folder Leetcode Solution	151
826	Total Numbers With no Repeated Digits in a Range	151
827	Growable array based stack	151
828	Subarray Product Less Than K LeetCode Solution	151
829	Maximum Profit in Job Scheduling Leetcode Solution	151
830	Form Minimum Number From Given Sequence	150
831	Convert BST to Min Heap	150
832	Brick Wall LeetCode Solution	150
833	Merge Sorted Array LeetCode Solution	150
834	Maximum Nesting Depth of the Parentheses Leetcode Solution	150
835	Regular Expression Matching	150
836	Circular Queue	150
837	Given an Array of Pairs Find all Symmetric Pairs in it	150
838	Alien Dictionary LeetCode Solution	150
839	Check if a given array can represent Preorder Traversal of Binary Search Tree	149
840	Path with maximum average value	149
841	Find All Possible Recipes from Given Supplies LeetCode Solution	149
842	Valid Parentheses Leetcode Solution	149
843	Subsequence of Size K With the Largest Even Sum LeetCode Solution	149
844	Longest Subarray Having Count of 1s One More than Count of 0s	149
845	Make Two Arrays Equal by Reversing Sub-arrays Leetcode Solution	149
846	Clone Graph LeetCode Solution	149
847	Sort Colors	149
848	Insert into a Binary Search Tree Leetcode Solution	149
849	Can Place Flowers LeetCode Solution	149
850	Friends Pairing Problem	149
851	Find the subarray with least average	149
852	Minimum Number of Taps to Open to Water a Garden LeetCode Solution	149
853	Check whether a given Binary Tree is Complete or not	149
854	Partition List Leetcode Solution	149
855	Top K Frequent Words LeetCode Solution	149
856	Count Distinct Elements in Every Window of Size K	148
857	Find the Only Repetitive Element Between 1 to N-1	148
858	Design a Stack With Increment Operation Leetcode Solution	148
859	Find Maximum Sum Possible Equal Sum of Three Stacks	148
860	Binary Search Tree Search and Insertion	148
861	Guess Number Higher or Lower LeetCode Solution	148
862	Sequences of given length where every element is more than or equal to twice of previous	148
863	Level order Traversal in Spiral Form	148
864	Matrix Chain Multiplication	148
865	Subset with sum divisible by m	148
866	Permutation Coefficient	148
867	Design Browser History LeetCode Solution	147
868	Repeated Substring Pattern LeetCode Solution	147
869	Distinct adjacent elements in an array	147
870	Water Bottles Leetcode Solution	147
871	Balanced Expression with Replacement	147
872	Minimum Sum Path in a Triangle	147
873	Sum of nearest smaller and greater number	147
874	Tree Traversal (Preorder, Inorder & Postorder)	147
875	Count Negative Numbers in a Sorted Matrix LeetCode Solution	147
876	Union and Intersection of two Linked Lists	146
877	Range LCM Queries	146
878	Maximum Score After Splitting a String Leetcode Solution	146
879	GCDs of given index ranges in an array	146
880	Daily Temperatures Leetcode Solution	146
881	K’th Largest Element in BST when modification to BST is not allowed	146
882	Rearrange an Array Such that arr[i] is equal to i	146
883	Diagonal Traverse LeetCode Solution	146
884	An Interesting Method to generate Binary Numbers from 1 to n	146
885	Number of Days Between Two Dates LeetCode Solution	146
886	Brightest Position on Street LeetCode Solution	146
887	Identify and Mark Unmatched Parenthesis in an Expression	146
888	Shortest Word Distance Leetcode Solution	146
889	LCS (Longest Common Subsequence) of three strings	146
890	BFS for Disconnected Graph	146
891	Best Time to Buy and Sell Stock with Transaction Fee Leetcode Solution	146
892	Sorted Array to Balanced BST	146
893	Minimum sum of multiplications of n numbers	146
894	Missing Element in Sorted Array LeetCode Solution	146
895	Diagonal Traversal LeetCode Solution	146
896	Three way partitioning of an array around a given range	146
897	Convert Sorted List to Binary Search Tree	145
898	Check if an Array is Stack Sortable	145
899	Delete And Earn	145
900	Minimum Swaps to Make Strings Equal Leetcode Solution	145
901	Least Number of Unique Integers after K Removals Leetcode Solution	145
902	Guess Number Higher or Lower II	145
903	Find distance between two nodes of a Binary Tree	145
904	Count ways to reach the nth stair using step 1, 2 or 3	145
905	Destination City Leetcode Solution	145
906	Insert Delete GetRandom	145
907	Check if the given array can represent Level Order Traversal of Binary Search Tree	145
908	Range sum queries without updates	145
909	Robot Bounded In Circle LeetCode Solution	145
910	Check if stack elements are pairwise consecutive	145
911	Lemonade Change Leetcode Solution	145
912	Rearrange Array such that arr[i] >= arr[j] if i is even and arr[i] <= arr[j] if i is odd and j < i	145
913	Merge Two Sorted Lists Leetcode	144
914	Print Fibonacci sequence using 2 variables	144
915	Palindrome Partitioning Leetcode Solution	144
916	Vertical sum in a given binary tree	144
917	Spiral Matrix III LeetCode Solution	144
918	Rearrange Spaces Between Words Leetcode Solution	144
919	4Sum	144
920	A program to check if a binary tree is BST or not	143
921	Maximum Frequency Stack Leetcode Solution	143
922	Alien Dictionary	143
923	Time Based Key-Value Store LeetCode Solution	143
924	Split Array Into Consecutive Subsequences	143
925	Special Positions in a Binary Matrix Leetcode Solution	143
926	Construct Complete Binary Tree from its Linked List Representation	143
927	Construct the Rectangle Leetcode Solution	143
928	3 Sum	143
929	Lexicographical Numbers Leetcode Solution	142
930	Iterative Postorder Traversal Using Two Stacks	142
931	Number of Distinct Islands Leetcode Solution	142
932	Check if any two intervals overlap among a given set of intervals	142
933	Queries for GCD of all numbers of an array except elements in a given range	142
934	Trim a Binary Search Tree	142
935	Remove Duplicates from Sorted List II LeetCode Solution	142
936	Set Matrix Zeroes Leetcode Solution	142
937	Find Common Characters Leetcode Solution	142
938	Construct BST from its given Level Order Traversal	142
939	Minimum Height Trees LeetCode Solution	142
940	Difference Array \| Range update query in O(1)	142
941	Averages of Levels in Binary Tree	142
942	Longest Palindromic Subsequence	142
943	Infix to Postfix	142
944	Binary Tree Longest Consecutive Sequence LeetCode Solution	142
945	Stone Game II Leetcode	142
946	Binary array after M range toggle operations	141
947	Strongly Connected Component	141
948	Count Subarrays with Same Even and Odd Elements	141
949	All Unique Triplets that Sum up to a Given Value	141
950	Find all permuted rows of a given row in a matrix	141
951	Unique Paths II	141
952	Analyze User Website Visit Pattern LeetCode Solution	141
953	Queue using Stacks	141
954	Largest area rectangular sub-matrix with equal number of 1’s and 0’s	141
955	Collect maximum points in a grid using two traversals	141
956	Shuffle 2n integers as a1-b1-a2-b2-a3-b3-..bn without using extra space	140
957	Create Maximum Number	140
958	Can Make Arithmetic Progression From Sequence Leetcode Solution	140
959	Pattern Occurrences using Stack	140
960	Reverse Nodes in K-Group	140
961	Word Break	140
962	Count subarrays where second highest lie before highest	140
963	Find postorder traversal of BST from preorder traversal	140
964	Intersection of Two Linked Lists LeetCode Solution	140
965	Merging Intervals	140
966	Minesweeper LeetCode Solution	140
967	Three Consecutive Odds Leetcode Solution	140
968	Sliding Window Maximum	140
969	Count Submatrices With All Ones LeetCode Solution	140
970	Number of Equivalent Domino Pairs Leetcode Solution	140
971	Kth Smallest Element in a BST Leetcode Solution	139
972	Longest Nice Substring LeetCode Solution	139
973	Binary Search Tree Delete Operation	139
974	Length of Longest Fibonacci Subsequence	139
975	Product of Array Except Self LeetCode Solution	139
976	Find the Difference Leetcode Solution	139
977	Maximum Product Subarray	139
978	Newman-Conway Sequence	139
979	Dividing Array into Pairs With Sum Divisible by K	139
980	Count pair with Given Sum	139
981	Palindrome Partitioning	139
982	Level Order Traversal of Binary Tree	139
983	Count Primes in Ranges	139
984	Height of a generic tree from parent array	139
985	Maximum Subarray Sum Excluding Certain Elements	139
986	Median of Two Sorted Arrays	138
987	Sign of the Product of an Array LeetCode Solution	138
988	Asteroid Collision LeetCode Solution	138
989	Maximize Sum of Array after K Negations Leetcode Solution	138
990	My Calendar I LeetCode Solution	138
991	K Closest Points to Origin Leetcode Solution	138
992	Symmetric Tree	138
993	Check If a Word Occurs As a Prefix of Any Word in a Sentence Leetcode Solution	138
994	The Maze III LeetCode Solution	137
995	Maximum Product of Indexes of Next Greater on Left and Right	137
996	Find Duplicate Subtrees	137
997	Climbing stairs	137
998	Largest divisible pairs subset	137
999	Segment Tree	137
1000	Valid Boomerang Leetcode Solution	137
1001	Find the First Circular Tour that visits all the Petrol Pumps	137
1002	Number Of Longest Increasing Subsequence	137
1003	Double the first element and move zero to end	137
1004	Maximum Length of Repeated Subarray	137
1005	Boundary Traversal of binary tree	137
1006	Find Maximum of Minimum for Every Window Size in a Given Array	137
1007	Friends Of Appropriate Ages LeetCode Solution	137
1008	Make The String Great Leetcode Solution	136
1009	Compute nCr % p	136
1010	Construct Binary Tree from given Parent Array representation	136
1011	Insertion in a Binary Tree	136
1012	The Painter’s Partition Problem	136
1013	Maximum weight transformation of a given string	136
1014	Largest Substring Between Two Equal Characters Leetcode Solution	136
1015	First missing positive	136
1016	Maximum subsequence sum such that no three are consecutive	136
1017	Boolean Parenthesization Problem	136
1018	String Matching in an Array Leetcode Solution	136
1019	Morris Inorder Traversal	136
1020	Largest Number Leetcode Solution	136
1021	Serialize and Deserialize Binary Tree	136
1022	Partition Equal Subset Sum	136
1023	Breadth First Search (BFS) for a Graph	136
1024	Level order traversal using two Queues	136
1025	Depth First Search (DFS) for a Graph	136
1026	Construction of Longest Increasing Subsequence (N log N)	136
1027	Maximum Number of Ways to Partition an Array LeetCode Solution	135
1028	Kill Process LeetCode Solution	135
1029	Next Greater Element III LeetCode Solution	135
1030	Rearrange an array such that ‘arr[j]’ becomes ‘i’ if ‘arr[i]’ is ‘j’	135
1031	Graph Valid Tree LeetCode Solution	135
1032	Shortest Completing Word Leetcode Solution	135
1033	Minimum Index Sum of Two Lists	135
1034	Decrypt String from Alphabet to Integer Mapping Leetcode Solution	135
1035	Longest subsequence such that difference between adjacents is one	135
1036	Binary Search Tree	135
1037	Rearrange array such that even positioned are greater than odd	134
1038	Build an Array With Stack Operations Leetcode Solution	134
1039	Custom Sort String Leetcode Solution	134
1040	Scramble String LeetCode Solution	134
1041	Maximum Sum of 3 Non-Overlapping Subarrays	134
1042	K maximum sums of overlapping contiguous sub-arrays	134
1043	Design Hit Counter LeetCode Solution	134
1044	Advantages of BST over Hash Table	134
1045	Ugly Numbers	134
1046	Validate Binary Search Tree	134
1047	Find number of pairs in an array such that their XOR is 0	134
1048	Number of palindromic paths in a matrix	134
1049	Balanced Binary Tree	133
1050	Invalid Transactions LeetCode Solution	133
1051	Ugly Number II LeetCode Solution	133
1052	Defanging an IP Address LeetCode Solution	133
1053	Available Captures for Rook Leetcode Solution	133
1054	Bitwise AND of Numbers Range LeetCode Solution	133
1055	Move all negative elements to end in order with extra space allowed	132
1056	Maximum length subsequence with difference between adjacent elements as either 0 or 1	132
1057	Iterative Depth First Traversal of Graph	132
1058	Search in Sorted Rotated Array	132
1059	Path Sum II LeetCode Solution	132
1060	Count pairs from two sorted arrays whose sum is equal to a given value x	132
1061	Count minimum steps to get the given desired array	132
1062	Employee Importance LeetCode Solution	132
1063	Add two numbers	132
1064	Implement Trie (Prefix Tree) Leetcode Solution	132
1065	Recover Binary Search Tree Leetcode Solution	132
1066	Lowest Common Ancestor	132
1067	Super Ugly Number	132
1068	Binary Tree Right Side View LeetCode Solution	131
1069	Largest BST Subtree LeetCode Solution	131
1070	Number of Students Doing Homework at a Given Time Leetcode Solution	131
1071	Find a Peak Element II LeetCode Solution	131
1072	Regular Expression Matching Regular Expression Matching LeetCode Solution	131
1073	Find Peak Element	131
1074	Generate Parentheses Leetcode Solution	131
1075	Remove Duplicates from Sorted Array II Leetcode Solution	131
1076	Maximum difference between frequency of two elements such that element having greater frequency is also greater	131
1077	Determine Whether Matrix Can Be Obtained By Rotation LeetCode Solution	131
1078	Subarrays with K Different Integers Leetcode Solution	130
1079	Smallest Common Region Leetcode Solution	130
1080	Kth Smallest Element in a Sorted Matrix LeetCode Solution	130
1081	Day of the Year Leetcode Solution	130
1082	Populating Next Right Pointers in Each Node Leetcode Solution	130
1083	Find whether a subarray is in form of a mountain or not	130
1084	Clone a Binary Tree with Random Pointers	130
1085	Root to Leaf path with target sum Leetcode Solutions	130
1086	Number of Closed Islands Leetcode Solution	130
1087	Rearrange array such that even index elements are smaller and odd index elements are greater	130
1088	Longest Bitonic Subsequence	130
1089	Combination Sum IV LeetCode Solution	130
1090	Increasing Triplet Subsequence LeetCode Solution	129
1091	Convert BST into a Min-Heap without using array	129
1092	Find Smallest Range Containing Elements from k Lists	129
1093	Number of siblings of a given Node in n-ary Tree	129
1094	Maximize Distance to Closest Person LeetCode Solution	129
1095	Serialize and Deserialize Binary Tree LeetCode Solution	129
1096	Minimum Size Subarray Sum	129
1097	Find the minimum distance between two numbers	129
1098	Remove Palindromic Subsequences Leetcode Solution	129
1099	Binary Tree Data Structure	129
1100	Next Permutation Leetcode Solution	129
1101	Distinct Subsequences	129
1102	Types of Binary Tree	129
1103	Kth Smallest Product of Two Sorted Arrays LeetCode Solution	129
1104	Consecutive Characters LeetCode Solution	129
1105	Count Largest Group Leetcode Solution	128
1106	Find Three Element From Different Three Arrays Such That a + b + c = sum	128
1107	Constant time range add operation on an array	128
1108	Path Sum	128
1109	Construct Binary Tree from Preorder and Postorder Traversal LeetCode Solution	128
1110	Divisible Pairs Counting	128
1111	Remove duplicates from sorted array	128
1112	Find maximum difference between nearest left and right smaller elements	128
1113	Print all triplets in sorted array that form AP	128
1114	Level of Each node in a Tree from source node	128
1115	Iterative method to find ancestors of a given binary tree	128
1116	Longest Subarray of 1’s After Deleting One Element LeetCode Solution	127
1117	Maximum Product Subarray	127
1118	Cutting a Rod	127
1119	Third Maximum Number Leetcode Solution	127
1120	Sum of Even Numbers After Queries	127
1121	Prime Palindrome LeetCode Solution	127
1122	Mean of Array After Removing Some Elements Leetcode Solution	126
1123	Cells with Odd Values in a Matrix LeetCode Solution	126
1124	Bottom View of a Binary Tree	126
1125	Valid Tic-Tac-Toe State LeetCode Solution	126
1126	Palindrome Permutation LeetCode Solution	126
1127	Reformat The String Leetcode Solution	126
1128	Minimum Absolute Difference in BST Leetcode Solution	126
1129	Print Right View of a Binary Tree	126
1130	Products of ranges in an array	126
1131	Print Next Greater Number of Q queries	126
1132	Minimum Score Triangulation of Polygon Leetcode Solution	126
1133	Delete Nodes and Return Forest Leetcode Solution	125
1134	Search an Element in Sorted Rotated Array	125
1135	Search Insert Position	125
1136	Topological Sorting	125
1137	Write Code to Determine if Two Trees are Identical	125
1138	Moser-de Bruijn Sequence	125
1139	Swap Nodes In Pairs	124
1140	Thousand Separator Leetcode Solution	124
1141	Subset Sum Problem in O(sum) space	124
1142	Construct K Palindrome Strings LeetCode Solution	124
1143	Maximum Binary Tree	124
1144	Merge two BSTs with limited extra space	124
1145	Palindromic Substrings Leetcode Solution	124
1146	Closest Binary Search Tree Value Leetcode Solution	124
1147	Minimum sum of squares of character counts in a given string after removing k characters	123
1148	Golomb sequence	123
1149	Print modified array after executing the commands of addition and subtraction	123
1150	Check Array Formation Through Concatenation Leetcode Solution	123
1151	Possible Bipartition LeetCode Solution	123
1152	Longest Increasing Consecutive Subsequence	123
1153	Diameter of N-Ary Tree LeetCode Solution	123
1154	Find Two Non-overlapping Sub-arrays Each With Target Sum LeetCode Solution	123
1155	Bus Routes Leetcode Solution	123
1156	Red-Black Tree Introduction	122
1157	Maximize sum of consecutive differences in a circular array	122
1158	Kth Smallest Number in Multiplication Table Leetcode Solution	122
1159	Priority Queue	122
1160	Maximum Product of Splitted Binary Tree LeetCode Solution	122
1161	Remove Max Number of Edges to Keep Graph Fully Traversable Leetcode Solution	122
1162	Queries for Number of Distinct Elements in a Subarray	122
1163	Find Largest Value in Each Tree Row LeetCode Solution	122
1164	Minimum Sideway Jumps LeetCode Solution	122
1165	Find a sorted subsequence of size 3 in linear time	122
1166	Transform a BST to Greater sum Tree	122
1167	Search Suggestions System LeetCode Solution	122
1168	Find maximum length Snake sequence	122
1169	Decision Tree	121
1170	Compare Strings by Frequency of the Smallest Character Leetcode Solution	121
1171	Find the smallest binary digit multiple of given number	121
1172	Binary Tree to Binary Search Tree Conversion	121
1173	Count even length binary sequences with same sum of first and second half bits	121
1174	Longest Repeated Subsequence	121
1175	Matchsticks to Square Leetcode Solution	120
1176	Factorial Trailing Zeroes LeetCode Solution	120
1177	Lowest Common Ancestor in Binary Search Tree	120
1178	Rotate Array	120
1179	Swapping Nodes in a Linked List Leetcode Solution	120
1180	Web Crawler LeetCode Solution	120
1181	First Bad Version	120
1182	Convert Sorted Array to Binary Search Tree LeetCode Solutions	120
1183	Maximum sum bitonic subarray	119
1184	K’th Largest element in BST using constant extra space	119
1185	Decrease Elements To Make Array Zigzag LeetCode Solution	119
1186	Queue Reconstruction by Height	119
1187	Number of Orders in the Backlog Leetcode Solution	119
1188	Minimum Cost to Move Chips to The Same Position LeetCode Solution	119
1189	Reverse a Path in BST using Queue	119
1190	Valid Triangle Number	118
1191	Closest Leaf in a Binary Tree LeetCode Solution	118
1192	Sum of Left Leaves LeetCode Solution	118
1193	Minimum Moves to Equal Array Elements LeetCode Solution	118
1194	Reformat Date LeetCode Solution	118
1195	Given a binary tree, how do you remove all the half nodes?	118
1196	Graph and its representation	118
1197	Maximum number of segments of lengths a, b and c	118
1198	Range Queries for Longest Correct Bracket Subsequence	118
1199	Moving Stones Until Consecutive Leetcode Solution	118
1200	Contiguous Array LeetCode Solution	118
1201	Maximum sum of pairs with specific difference	118
1202	Count Pairs Whose Products Exist in Array	118
1203	Guess The Word	117
1204	Array Queries for multiply replacements and product	117
1205	How to print maximum number of A’s using given four keys	117
1206	Kth Smallest Element in a BST	117
1207	Filter Restaurants by Vegan-Friendly, Price and Distance Leetcode Solution	116
1208	Lowest Common Ancestor of a Binary Tree Leetcode Solution	116
1209	Replace two consecutive equal values with one greater	116
1210	Convert Integer to the Sum of Two No-Zero Integers Leetcode Solution	116
1211	Champagne Tower LeetCode Solution	116
1212	Path Crossing Leetcode Solution	116
1213	Concatenation of Array LeetCode Solution	115
1214	Perfect Squares LeetCode Solution	115
1215	Minimum Swaps To Make Sequences Increasing LeetCode Solution	115
1216	Integer Break LeetCode Solution	115
1217	Arithmetic Slices II – Subsequence LeetCode Solution	115
1218	Write a function to get the intersection point of two Linked Lists	114
1219	Flatten 2D Vector LeetCode Solution	114
1220	Check Completeness of a Binary Tree LeetCode Solution	114
1221	Design Skiplist LeetCode Solution	114
1222	LRU Cache Leetcode Solution	114
1223	Power of Two	114
1224	Divide Two Integers Leetcode Solution	114
1225	The kth Factor of n Leetcode Solution	114
1226	Maximum Depth Of Binary Tree	114
1227	Maximum sum of a path in a Right Number Triangle	114
1228	Range Sum Query using Sparse Table	114
1229	Merge Sort	114
1230	Longest Common Prefix Using Word by Word Matching	113
1231	Check if all levels of two Binary Tree are anagrams or not	113
1232	Largest Plus Sign Leetcode Solution	113
1233	BST to a Tree with Sum of all Smaller Keys	113
1234	Check for Identical BSTs without building the trees	113
1235	Contiguous Array	113
1236	Print modified array after multiple array range increment operations	113
1237	New 21 Game	113
1238	Maximize Elements Using Another Array	113
1239	Valid Perfect Square LeetCode Solution	113
1240	Queries on Probability of Even or Odd Number in given Ranges	113
1241	Find Minimum in Rotated Sorted Array II LeetCode Solution	113
1242	Mean of range in array	113
1243	Sliding Window Median Leetcode Solution	112
1244	Maximum Value at a Given Index in a Bounded Array LeetCode Solution	112
1245	Bold Words in String LeetCode Solution	112
1246	Print Ancestors of a Given Binary Tree Node Without Recursion	112
1247	Check if each internal node of a BST has exactly one child	112
1248	Print n terms of Newman-Conway Sequence	112
1249	Parallel Courses II LeetCode Solution	112
1250	Symmetric Tree LeetCode Solution Leetcode Solution	111
1251	Graph Cloning	111
1252	Maximum Array from Two given Arrays Keeping Order Same	111
1253	Find minimum number of merge operations to make an array palindrome	111
1254	Find k-th smallest element in BST (Order Statistics in BST)	111
1255	Count Subsets Having Distinct Even Numbers	111
1256	Merge k Sorted Lists Leetcode Solution	111
1257	Minimum Remove to Make Valid Parentheses LeetCode Solution	110
1258	Maximum Product Subarray	110
1259	Missing Number	110
1260	Count and Toggle Queries on a Binary Array	110
1261	Smallest Range II Leetcode Solution	110
1262	Check if two nodes are on the same path in a Tree	110
1263	Number of elements less than or equal to a given number in a given subarray	109
1264	Verify Preorder Serialization of a Binary Tree	109
1265	Image Overlap LeetCode Solution	108
1266	Next greater element	108
1267	Excel Sheet Column Title LeetCode Solution	108
1268	Check If a String Can Break Another String Leetcode Solution	108
1269	Koko Eating Bananas LeetCode Solution	107
1270	Orderly Queue LeetCode Solution	107
1271	Min Cost Climbing Stairs LeetCode Solution	107
1272	Palindrome Partitioning	107
1273	Different Ways to Add Parentheses Leetcode Solution	106
1274	Minimum Time to Collect All Apples in a Tree LeetCode Solution	106
1275	Check if X can give change to every person in the Queue	105
1276	Peeking Iterator LeetCode Solution	105
1277	Longest Substring Without Repeating Characters Leetcode Solution	104
1278	Newman–Shanks–Williams prime	103
1279	Merge Sorted Array	103
1280	Check in binary array the number represented by a subarray is odd or even	103
1281	Largest Submatrix With Rearrangements LeetCode Solution	102
1282	Range Minimum Query (Square Root Decomposition and Sparse Table)	102
1283	Array Nesting Leetcode Solution	102
1284	Arranging Coins Leetcode Solution	101
1285	Encoded String With Shortest Length LeetCode Solution	100
1286	Maximum Sum Increasing Subsequence	100
1287	Find maximum average subarray of k length	100
1288	Maximum product of an increasing subsequence	99
1289	Queries for Decimal Values of Subarrays of a Binary Array	99
1290	Minimum Total Space Wasted With K Resizing Operations LeetCode Solution	99
1291	Number of indexes with equal elements in given range	99
1292	Convert to Base -2 LeetCode Solution	98
1293	Minimum Number of People to Teach LeetCode Solution	98
1294	Convert a BST to a Binary Tree such that sum of all greater keys is added to every key	97
1295	Random Pick Index LeetCode Solution	97
1296	Binary Tree to Binary Search Tree Conversion using STL set	96
1297	Add Two Numbers II Leetcode Solution	96
1298	Vertical Order Traversal of Binary Tree LeetCode Solution	96
1299	Find the Winner of the Circular Game LeetCode Solution	96
1300	Continuous Subarray Sum LeetCode Solution	96
1301	Reach a Number LeetCode Solution	96
1302	Palindrome Number LeetCode Solution	95
1303	Queries on XOR of greatest odd divisor of the range	95
1304	Check given array of size n can represent BST of n levels or not	95
1305	Minimum Possible Integer After at Most K Adjacent Swaps On Digits LeetCode Solution	94
1306	Number of Subsequences That Satisfy the Given Sum Condition LeetCode solution	94
1307	Jump Game IV LeetCode Solution	94
1308	Insert Delete GetRandom O(1) Leetcode Solution	93
1309	Design Underground System Leetcode Solution	90
1310	Print Maximum Length Chain of Pairs	89
1311	Detect Capital Leetcode Solution	87
1312	Design A Leaderboard Leetcode Solution	86
1313	Top K Frequent Elements LeetCode Solution	83
1314	Minimum Swaps to Group All 1’s Together Leetcode Solution	83
1315	Substring with Concatenation of All Words Leetcode Solution	83
1316	Minimum Path Sum Leetcode Solution	80
1317	Count Sub Islands LeetCode Solution	80
1318	Binary Tree Inorder Traversal LeetCode Solution	80
1319	Shifting Letters LeetCode Solution	79
1320	Longest Common Subsequence LeetCode Solution	77
1321	Odd Even Linked List Leetcode Solution	77
1322	Best Meeting Point LeetCode Solution	76
1323	Find the Town Judge LeetCode Solution	76
1324	Find the Town Judge LeetCode Solution	75
1325	Decode String Leetcode Solution	75
1326	Maximum Population Year LeetCode Solution	74
1327	Shortest Unsorted Continuous Subarray LeetCode Solution	72
1328	Sum Root to Leaf Numbers LeetCode Solution	71
1329	Maximum Population Year LeetCode Solution	71
1330	Design Add and Search Words Data Structure LeetCode Solution	70
1331	Rectangle Overlap LeetCode Solution	70
1332	Flatten Binary Tree to Linked List LeetCode Solution	67
1333	Stone Game IV LeetCode Solution	67
1334	Range Sum Query 2D – Immutable LeetCode Solution	66
1335	Score of Parenthesis LeetCode Solution	66
1336	Insert into a Sorted Circular Linked List LeetCode Solution	66
1337	Reveal Cards In Increasing Order Leetcode Solution	63
1338	Is Graph Bipartite? LeetCode Solution	62
1339	Valid Triangle Number LeetCode Solution	62
1340	Divide Chocolate LeetCode Solution	53
1341	Step-By-Step Directions From a Binary Tree Node to Another LeetCode Solution	48
1342	Range Sum of BST LeetCode Solution	45
1343	Reverse Integer Leetcode Solution	43
1344	Sort Colors LeetCode Solution	42
1345	Find K Closest Elements LeetCode Solution	40
1346	Maximum Side Length of a Square with Sum Less than or Equal to Threshold LeetCode Solution	38
1347	Excel Sheet Column Number LeetCode Solution	37
1348	Rotate String LeetCode Solution	37
1349	Maximum Size Subarray Sum Equals k Leetcode Solution	19
1350	High Five LeetCode Solution	18
1351	H-Index Leetcode Solution	18
1352	Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution	3