Stone Game IV LeetCode Solution

Difficulty Level Hard
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Problem Statement:

Stone Game IV LeetCode Solution : Alice and Bob take turns playing a game, with Alice starting first.

Initially, there are n stones in a pile. On each player’s turn, that player makes a move consisting of removing any non-zero square number of stones in the pile.

Also, if a player cannot make a move, he/she loses the game.

Given a positive integer n, return true if and only if Alice wins the game otherwise return false, assuming both players play optimally.


Example 1:


 n = 1




Alice can remove 1 stone winning the game because Bob doesn't have any moves.

Example 2:


 n = 2




Alice can only remove 1 stone, after that Bob removes the last one winning the game (2 -> 1 -> 0).

Example 3:


 n = 4




 n is already a perfect square, Alice can win with one move, removing 4 stones (4 -> 0).



We will be solving the problem with the concept of dynamic programming. First, we can generate the recursive solution and then can optimize it using memorization.

The idea is to iterate over all possible movements and check whether we can reach a False state or not. If we can, then it means we have found a must-win strategy, else we must lose since the opponent has found a must-win strategy.

Stone Game IV LeetCode SolutionPin


Stone Game IV C++ Solution:

class Solution {
    int dp[100005];
    bool helper(int n){
            return true;
            return false;
        if(dp[n] != -1)
            return dp[n];
        bool alice = false;
        for(int i=1;i<=sqrt(n);i++){
            bool bob = helper(n-i*i);
            if(not bob){
                alice = true;
        return dp[n] = alice;
    bool winnerSquareGame(int n) {
        return helper(n);

Stone Game IV Python Solution:

class Solution:
    def winnerSquareGame(self, n: int) -> bool:
        dp = [False]*(n+1)
        for i in range(1, n+1):
            for k in range(1, int(i**0.5)+1):
                if dp[i-k*k] == False:
                    dp[i] = True
        return dp[n]

Complexity Analysis of Stone Game IV LeetCode Solution:

  • Time Complexity: The time complexity of the above code is O(n√n).
  • Space Complexity: The space complexity of the above code is O(n).

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604Iterative Method to find Height of Binary Tree204
605Minimum number of distinct elements after removing m items203
606Sieve of Eratosthenes203
607Non-overlapping sum of two sets203
608Word Pattern203
609Island Perimeter Leetcode Solution203
610Count all subsequences having product less than K203
611Remove Linked List Elements Leetcode Solution203
612Assign Cookies Leetcode Solution202
613Find minimum difference between any two elements202
614Find the smallest positive integer value that cannot be represented as sum of any subset of a given array202
615XOR Operation in an Array Leetcode Solution202
616Stone Game LeetCode201
617Reverse a stack without using extra space in O(n)201
618Bubble sort using two Stacks201
619Convert Sorted Array to Binary Search Tree Leetcode Solution201
620Rotate List Leetcode Solution201
621GCD Of Two Numbers201
622Insert Interval Leetcode Solution201
623Minimum insertions to form a palindrome with permutations allowed201
624Permutation in String Leetcode Solution200
625The Knapsack Problem200
626Same Tree LeetCode Solution200
627Find Largest d in Array such that a + b + c = d200
628Sum of f(a[i], a[j]) over all pairs in an array of n integers200
629Applications of Breadth First Search and Depth First Search200
630Unique Binary Search Trees200
631Tracking current Maximum Element in a Stack200
632Reorganize String199
633Distance Between Bus Stops Leetcode Solution199
634Find the Duplicate Number LeetCode Solution199
635Defanging an IP Address Leetcode Solution199
636Maximum Number of Chocolates to be Distributed Equally Among k Students199
637Isomorphic Strings199
638Count Good Nodes in Binary Tree Leetcode Solution199
639Longest Increasing Path in a Matrix LeetCode Solution199
640License Key Formatting Leetcode Solution198
641Printing brackets in Matrix Chain Multiplication Problem198
642Optimal Account Balancing LeetCode Solution198
643Form minimum number from given sequence198
644Convert an array to reduced form198
645First Unique Character in a String LeetCode Solution198
646How to Create Mergable Stack?198
647K Empty Slots198
648Employee Free Time LeetCode Solution197
649Letter Combinations of a Phone Number197
650Minimum Depth of Binary Tree Leetcode Solution197
651Find pairs with given sum such that elements of pair are in different rows196
652Replace Elements with Greatest Element on Right Side Leetcode Solution196
653Sort Array By Parity LeetCode Solution196
654Reducing Dishes LeetCode Solution196
655Convert a Number to Hexadecimal Leetcode Solution196
656Minimum Number of Steps to Make Two Strings Anagram Leetcode Solutions196
657House Robber195
658Merge Two Balanced Binary Search Trees195
659Word Wrap Problem195
660K Empty Slots LeetCode195
661Longest Substring with At Most K Distinct Characters LeetCode Solution195
662Painting Fence Algorithm195
663Check If It Is a Straight Line Leetcode Solution195
664Robot Room Cleaner Leetcode Solution195
665Maximum Consecutive Numbers Present in an Array195
666Strobogrammatic Number LeetCode Solution195
667Find Pair with Greatest Product in Array195
668Partition Labels LeetCode Solution194
669Largest subarray with equal number of 0s and 1s194
670Segregate 0s and 1s in an Array194
671Queries for counts of array elements with values in given range194
672Coin Change Problem194
673Moving Average from Data Stream Leetcode Solution194
674Kth Missing Positive Number Leetcode Solution194
675String to Integer (atoi) LeetCode Solution193
676Longest Substring with At Least K Repeating Characters LeetCode Solution193
677Find Maximum Level sum in Binary Tree193
678Reservoir Sampling193
679Valid Palindrome II Leetcode Solution193
680Longest Span with same Sum in two Binary arrays193
681Find the node with minimum value in a Binary Search Tree193
682Maximum Product of Two Elements in an Array Leetcode Solution193
683Sum of All Odd Length Subarrays Leetcode Solution193
684Distance of nearest cell having 1 in a binary matrix193
685Power of Four Leetcode Solution192
686Print the Fibonacci numbers in reverse order192
687Dynamic Programming Basics192
688Flipping an Image LeetCode Solution192
689Valid Palindrome192
690Partition Array Into Three Parts With Equal Sum Leetcode Solution192
691Best Time to Buy and Sell Stock with Cooldown Leetcode Solution192
692Find the Distance Value Between Two Arrays Leetcode Solution192
693String Compression LeetCode Solution192
694Find unique character in a string191
695Remove Invalid Parentheses Leetcode Solution191
696Find the Smallest Divisor given a Threshold Leetcode Solution191
697Find Leaves of Binary Tree LeetCode Solution191
698Check If Two String Arrays are Equivalent Leetcode Solution191
699Generate all possible sorted arrays from alternate elements of two given sorted arrays191
700Binary Tree Maximum Path Sum LeetCode Solution190
701Delete Nth node from the end of the given linked list190
702Unique Paths II Leetcode Solution190
703To Lower Case Leetcode Solution190
704Find the largest multiple of 3190
705Path With Maximum Minimum Value LeetCode Solution190
706Wiggle Sort190
707Reverse Only Letters LeetCode Solution190
708Number of Dice Rolls With Target Sum LeetCode Solution190
709Increasing Decreasing String Leetcode Solution190
710Inorder Successor of a node in Binary Tree190
711Numbers with prime frequencies greater than or equal to k190
712Edit Distance LeetCode Solution189
713Lucky Numbers in a Matrix Leetcode Solution189
714Sort Array by Increasing Frequency Leetcode Solution189
715Subset Sum Leetcode189
716Stack Permutations (Check if an array is stack permutation of other)189
717Maximum Number of Coins You Can Get Leetcode Solution189
718Factorial Trailing Zeroes Leetcode Solution189
719Find whether an array is subset of another array189
720Non-decreasing Array LeetCode Solution189
721Rearrange an array in order – smallest, largest, 2nd smallest, 2nd largest189
722Populating Next Right Pointers in Each Node188
723Recover Binary Search Tree188
724k-th missing element in increasing sequence which is not present in a given sequence188
725Merge Two Binary Trees LeetCode Solution188
726Snakes and Ladders LeetCode Solution188
727Find if Path Exists in Graph Leetcode Solution188
728Permutation Sequence LeetCode Solution188
729Bulb Switcher LeetCode Solution188
730Remove brackets from an algebraic string containing + and – operators188
731Perform String Shifts Leetcode188
732BFS vs DFS for Binary Tree188
733Race Car LeetCode Solution188
734Reversing a Queue using Recursion188
735Count quadruples from four sorted arrays whose sum is equal to a given value x188
736Find Maximum Depth of Nested Parenthesis in a String187
737Maximum 69 Number Leetcode Solution187
738Evaluate Reverse Polish Notation LeetCode Solution187
739Majority Element II Leetcode Solution187
740Binary Tree Zigzag Level Order Traversal LeetCode Solution187
741Valid Perfect Square Leetcode Solution187
742Ugly Number Leetcode Solution187
743Maximum Length of a Concatenated String with Unique Characters Leetcode Solution187
744Minimum Cost For Tickets Leetcode Solution187
745Tiling Problem187
746Merge Sorted Array LeetCode Solution187
747Student Attendance Record I Leetcode Solution186
748Keyboard Row Leetcode Solution186
749Number of NGEs to the Right186
750Binary Tree zigzag level order Traversal186
751Base 7 Leetcode Solution186
752Word Pattern LeetCode Solution186
753String comparison containing wildcards186
754N-Queens LeetCode Solution186
755Best Meeting Point LeetCode Solution186
756Print a Binary Tree in Vertical Order186
757Valid Number186
758Symmetric Tree Leetcode Solution185
759Finding K closest element185
760Rank Transform of an Array Leetcode Solution185
761Growable array based stack185
762Elements to be added so that all elements of a range are present in array185
763Maximum Product of Three Numbers LeetCode Solution185
764Hamming Distance Leetcode Solution185
765Maximum Profit in Job Scheduling Leetcode Solution185
766Split a String in Balanced Strings Leetcode Solution185
767Morris Traversal185
768Add and Search Word – Data structure design LeetCode185
769Program for Bridge and Torch problem185
770Find All Possible Recipes from Given Supplies LeetCode Solution185
771Check if Two Expressions With Brackets are Same185
772Construct BST from given Preorder Traversal185
773Restore IP Addresses Leetcode Solution185
774Find Median from Data Stream LeetCode Solution185
775Minimum sum of multiplications of n numbers184
776Find All Duplicates in an Array LeetCode Solution184
777Binomial Coefficient184
778Regular Expression Matching184
779Check If Array Pairs Are Divisible by k LeetCode Solution184
780Number of Days Between Two Dates LeetCode Solution184
781Partition to K Equal Sum Subsets Leetcode Solution184
782Minimize Maximum Pair Sum in Array LeetCode Solution184
783Priority Queue using doubly linked list184
784Special Array With X Elements Greater Than or Equal X Leetcode Solution184
785Sorted Linked List to Balanced BST184
786Brick Wall LeetCode Solution184
787Top K Frequent Words LeetCode Solution184
788Decompress Run-Length Encoded List Leetcode Solution183
789Merge K Sorted Linked Lists183
790Jump Game183
791Sort an array according to the order defined by another array183
792Search in a Binary Search Tree Leetcode Solution183
793Largest Rectangle in Histogram LeetCode Solution183
794Form Minimum Number From Given Sequence183
795Minimum Distance Between BST Nodes Leetcode Solution183
796Check for Palindrome after every character replacement Query183
797Maximum Depth of N-ary Tree Leetcode Solution182
798Queue based approach for first non-repeating character in a stream182
799Maximum Difference Between Increasing Elements LeetCode Solution182
800Kth ancestor of a node in binary tree182
801Nearest Exit from Entrance in Maze LeetCode Solution182
802Total Numbers With no Repeated Digits in a Range182
803Linked List Cycle182
804Longest Subarray Having Count of 1s One More than Count of 0s182
805Minimum Height Trees182
806Largest rectangular sub-matrix whose sum is 0182
807Invert Binary Tree LeetCode Solution182
808One Edit Distance LeetCode Solution182
809Minimum Time Visiting All Points Leetcode Solution182
810Remove Nth Node From End of List Leetcode Solution181
811Maximum Nesting Depth of the Parentheses Leetcode Solution181
812Circular Queue181
813Balanced Expression with Replacement181
814Final Prices With a Special Discount in a Shop Leetcode Solution181
815Identify and Mark Unmatched Parenthesis in an Expression181
816Number of Islands II LeetCode Solution181
817Count items common to both the lists but with different prices181
818Minimum time required to rot all oranges180
819Nested List Weight Sum II LeetCode Solution180
820Relative Ranks Leetcode Solution180
821Repeated Substring Pattern LeetCode Solution180
822Transpose Graph180
823Diagonal Traversal of Binary Tree180
824Given an Array of Pairs Find all Symmetric Pairs in it180
825Crawler Log Folder Leetcode Solution179
826Daily Temperatures Leetcode Solution179
827Minimum Swaps to Make Strings Equal Leetcode Solution179
828Minimum Jumps to Reach Home LeetCode Solution179
829Permutation Coefficient179
830Deletion in a Binary Tree179
831Make Two Arrays Equal by Reversing Sub-arrays Leetcode Solution179
832Search a 2D Matrix II Leetcode Solution179
833Minimum Number of Taps to Open to Water a Garden LeetCode Solution179
834Course Schedule II – LeetCode178
835Split Array Into Consecutive Subsequences178
836Design Browser History LeetCode Solution178
837Subsequence of Size K With the Largest Even Sum LeetCode Solution178
838Subarray Product Less Than K LeetCode Solution178
839Reorder Data in Log Files LeetCode Solution178
840LCS (Longest Common Subsequence) of three strings178
841Clone Graph LeetCode Solution178
842Number Complement Leetcode Solution178
843Sort Array By Parity II Leetcode Solution178
844Check if an Array is Stack Sortable177
845A Space Optimized DP solution for 0-1 Knapsack Problem177
846Last Stone Weight II LeetCode Solution177
847Lemonade Change Leetcode Solution177
848Iterative Preorder Traversal177
849Insert Delete GetRandom177
850Check if stack elements are pairwise consecutive177
851Binary Search Tree Search and Insertion177
852Find Maximum Sum Possible Equal Sum of Three Stacks177
853Sliding Window Maximum177
854Remove Duplicates from Sorted List II177
855Find all permuted rows of a given row in a matrix177
856Distinct adjacent elements in an array177
857Missing Element in Sorted Array LeetCode Solution177
858Tree Traversal (Preorder, Inorder & Postorder)176
859Minimum Sum Path in a Triangle176
860Valid Parentheses Leetcode Solution176
861Matrix Chain Multiplication176
862Find the Only Repetitive Element Between 1 to N-1176
863Union and Intersection of two Linked Lists176
864An Interesting Method to generate Binary Numbers from 1 to n176
865Check if a given array can represent Preorder Traversal of Binary Search Tree176
866Subset with sum divisible by m176
867Path with maximum average value176
868Alien Dictionary LeetCode Solution176
869Guess Number Higher or Lower LeetCode Solution176
870Count Distinct Elements in Every Window of Size K176
871Minimum number of jumps to reach end176
872Interval Tree175
873Sorted Array to Balanced BST175
874Remove Duplicates from Sorted List LeetCode Solution175
875Dividing Array into Pairs With Sum Divisible by K175
876Spiral Matrix II Leetcode Solution175
877Count ways to reach the nth stair using step 1, 2 or 3175
878Convert BST to Min Heap175
879Partition List Leetcode Solution175
880Get Maximum in Generated Array Leetcode Solution175
881Can Place Flowers LeetCode Solution175
882Find the subarray with least average175
883Design a Stack With Increment Operation Leetcode Solution175
884Minimum swaps to make sequences increasing175
885Sort Colors174
886Number of Distinct Islands Leetcode Solution174
887Infix to Postfix174
888Minesweeper LeetCode Solution174
889Sum of nearest smaller and greater number174
890Brightest Position on Street LeetCode Solution174
891Least Number of Unique Integers after K Removals Leetcode Solution174
892GCDs of given index ranges in an array174
893Sequences of given length where every element is more than or equal to twice of previous174
894Check whether a given Binary Tree is Complete or not174
895Level order Traversal in Spiral Form174
896Friends Pairing Problem173
897Water Bottles Leetcode Solution173
898Diagonal Traverse LeetCode Solution173
899Median of Two Sorted Arrays173
900Rearrange Array such that arr[i] >= arr[j] if i is even and arr[i] <= arr[j] if i is odd and j < i173
901Maximum Score After Splitting a String Leetcode Solution173
902Find all triplets with zero sum173
903Diagonal Traversal LeetCode Solution173
904Pattern Occurrences using Stack173
905Guess Number Higher or Lower II173
906Range sum queries without updates173
907Find distance between two nodes of a Binary Tree173
908Iterative Postorder Traversal Using Two Stacks173
909Maximum size subarray sum equals k173
910Insert into a Binary Search Tree Leetcode Solution172
911Time Based Key-Value Store LeetCode Solution172
912Set Matrix Zeroes Leetcode Solution172
913Destination City Leetcode Solution172
914Lexicographical Numbers Leetcode Solution172
915Shortest Word Distance Leetcode Solution172
916Delete And Earn172
917Range LCM Queries172
918Count Negative Numbers in a Sorted Matrix LeetCode Solution172
919Rearrange an Array Such that arr[i] is equal to i172
920Check if any two intervals overlap among a given set of intervals172
921Best Time to Buy and Sell Stock with Transaction Fee Leetcode Solution172
922All Unique Triplets that Sum up to a Given Value171
923Difference Array | Range update query in O(1)171
924Averages of Levels in Binary Tree171
925Robot Bounded In Circle LeetCode Solution171
926Alien Dictionary171
927A program to check if a binary tree is BST or not171
928Construct Complete Binary Tree from its Linked List Representation170
929Find Common Characters Leetcode Solution170
930Spiral Matrix III LeetCode Solution170
931Product of Array Except Self LeetCode Solution170
932Rearrange Spaces Between Words Leetcode Solution170
933Construct the Rectangle Leetcode Solution170
934K’th Largest Element in BST when modification to BST is not allowed170
935Binary Tree Longest Consecutive Sequence LeetCode Solution170
936My Calendar I LeetCode Solution170
937Three way partitioning of an array around a given range170
938Special Positions in a Binary Matrix Leetcode Solution170
939Check if the given array can represent Level Order Traversal of Binary Search Tree170
940Count Submatrices With All Ones LeetCode Solution170
941Convert Sorted List to Binary Search Tree169
942Intersection of Two Linked Lists LeetCode Solution169
943Queue using Stacks169
944Create Maximum Number169
945Trim a Binary Search Tree169
946Analyze User Website Visit Pattern LeetCode Solution169
947Maximum Frequency Stack Leetcode Solution169
948Vertical sum in a given binary tree169
949Merge Two Sorted Lists Leetcode169
950Three Consecutive Odds Leetcode Solution169
951Minimum Height Trees LeetCode Solution169
952Binary array after M range toggle operations169
953Palindrome Partitioning Leetcode Solution169
954Number of Equivalent Domino Pairs Leetcode Solution169
955Count Subarrays with Same Even and Odd Elements169
956Remove Duplicates from Sorted List II LeetCode Solution168
957BFS for Disconnected Graph168
958Largest area rectangular sub-matrix with equal number of 1’s and 0’s168
959Maximize Sum of Array after K Negations Leetcode Solution168
960Word Break168
961Strongly Connected Component168
962Longest Palindromic Subsequence168
963Queries for GCD of all numbers of an array except elements in a given range168
964Reverse Nodes in K-Group167
965Count subarrays where second highest lie before highest167
966Sign of the Product of an Array LeetCode Solution167
967Maximum Product Subarray167
968Climbing stairs167
970Count Primes in Ranges167
9713 Sum167
972Longest subsequence such that difference between adjacents is one167
973Kth Smallest Element in a BST Leetcode Solution167
974Construct BST from its given Level Order Traversal167
975Depth First Search (DFS) for a Graph167
976Unique Paths II166
977Combination Sum IV LeetCode Solution166
978Merging Intervals166
979Stone Game II Leetcode166
980Number of palindromic paths in a matrix166
981Symmetric Tree166
982Print Fibonacci sequence using 2 variables166
983Count pair with Given Sum166
984Find Maximum of Minimum for Every Window Size in a Given Array165
985Largest Number Leetcode Solution165
986The Maze III LeetCode Solution165
987Design Hit Counter LeetCode Solution165
988Scramble String LeetCode Solution165
989String Matching in an Array Leetcode Solution165
990Breadth First Search (BFS) for a Graph165
991Maximum Subarray Sum Excluding Certain Elements165
992Serialize and Deserialize Binary Tree165
993Longest Nice Substring LeetCode Solution165
994Find number of pairs in an array such that their XOR is 0164
995Binary Search Tree Delete Operation164
996Maximum Length of Repeated Subarray164
997Height of a generic tree from parent array164
998Asteroid Collision LeetCode Solution164
999Valid Boomerang Leetcode Solution164
1000Next Permutation Leetcode Solution164
1001Find the First Circular Tour that visits all the Petrol Pumps164
1002Palindrome Partitioning164
1003Maximum Product of Indexes of Next Greater on Left and Right164
1004Can Make Arithmetic Progression From Sequence Leetcode Solution164
1005Find the Difference Leetcode Solution164
1006Largest Substring Between Two Equal Characters Leetcode Solution164
1007Print Next Greater Number of Q queries163
1008Shortest Completing Word Leetcode Solution163
1009K Closest Points to Origin Leetcode Solution163
1010Count pairs from two sorted arrays whose sum is equal to a given value x163
1011Graph Valid Tree LeetCode Solution163
1012Kth Smallest Element in a Sorted Matrix LeetCode Solution163
1013K maximum sums of overlapping contiguous sub-arrays163
1014Consecutive Characters LeetCode Solution163
1015Remove Duplicates from Sorted Array II Leetcode Solution163
1016Maximum Sum of 3 Non-Overlapping Subarrays162
1017Generate Parentheses Leetcode Solution162
1018Length of Longest Fibonacci Subsequence162
1019Maximum length subsequence with difference between adjacent elements as either 0 or 1162
1020Balanced Binary Tree162
1021Invalid Transactions LeetCode Solution162
1022Friends Of Appropriate Ages LeetCode Solution162
1023Collect maximum points in a grid using two traversals162
1024The Painter’s Partition Problem162
1025Minimum Index Sum of Two Lists162
1026Shuffle 2n integers as without using extra space162
1027Level Order Traversal of Binary Tree162
1028Maximum difference between frequency of two elements such that element having greater frequency is also greater162
1029Find postorder traversal of BST from preorder traversal162
1030Validate Binary Search Tree162
1031Newman-Conway Sequence162
1032Decrypt String from Alphabet to Integer Mapping Leetcode Solution162
1033Maximum Number of Ways to Partition an Array LeetCode Solution162
1034Find Duplicate Subtrees161
1035Rearrange an array such that ‘arr[j]’ becomes ‘i’ if ‘arr[i]’ is ‘j’161
1036Merge Sort161
1037Number Of Longest Increasing Subsequence161
1038Next Greater Element III LeetCode Solution161
1039Largest divisible pairs subset161
1040Segment Tree161
1041Available Captures for Rook Leetcode Solution161
1042Move all negative elements to end in order with extra space allowed161
1043Check If a Word Occurs As a Prefix of Any Word in a Sentence Leetcode Solution161
1044Boolean Parenthesization Problem161
1045Make The String Great Leetcode Solution161
1046Insertion in a Binary Tree160
1047Binary Search Tree160
1048Construct Binary Tree from given Parent Array representation160
1049Construction of Longest Increasing Subsequence (N log N)160
1050Compute nCr % p160
1051Bitwise AND of Numbers Range LeetCode Solution160
1052Find a Peak Element II LeetCode Solution160
1053Advantages of BST over Hash Table160
1054First missing positive160
1055Custom Sort String Leetcode Solution160
1056Kill Process LeetCode Solution160
1057Count minimum steps to get the given desired array159
1058Iterative Depth First Traversal of Graph159
1059Print Right View of a Binary Tree159
1060Rearrange array such that even index elements are smaller and odd index elements are greater159
1061Determine Whether Matrix Can Be Obtained By Rotation LeetCode Solution159
1062Build an Array With Stack Operations Leetcode Solution159
1063Boundary Traversal of binary tree159
1064Rearrange array such that even positioned are greater than odd159
1065Employee Importance LeetCode Solution158
1066Double the first element and move zero to end158
1067Path Sum II LeetCode Solution158
1068Largest BST Subtree LeetCode Solution158
1069Maximum subsequence sum such that no three are consecutive158
1070Defanging an IP Address LeetCode Solution158
1071Subarrays with K Different Integers Leetcode Solution158
1072Minimum Size Subarray Sum158
1073Level order traversal using two Queues157
1074Remove Palindromic Subsequences Leetcode Solution157
1075Partition Equal Subset Sum157
1076Add two numbers157
1077Morris Inorder Traversal157
1078Recover Binary Search Tree Leetcode Solution157
1079Regular Expression Matching Regular Expression Matching LeetCode Solution157
1080Find Peak Element157
1081Maximum weight transformation of a given string157
1082Palindrome Permutation LeetCode Solution156
1083Binary Tree Right Side View LeetCode Solution156
1084Find whether a subarray is in form of a mountain or not156
1085Smallest Common Region Leetcode Solution156
1086Ugly Numbers156
1087Lowest Common Ancestor156
1088Ugly Number II LeetCode Solution156
1089Implement Trie (Prefix Tree) Leetcode Solution156
1090Find maximum difference between nearest left and right smaller elements156
1091Increasing Triplet Subsequence LeetCode Solution155
1092Populating Next Right Pointers in Each Node Leetcode Solution155
1093Palindromic Substrings Leetcode Solution155
1094Longest Bitonic Subsequence155
1095Bus Routes Leetcode Solution155
1096Super Ugly Number155
1097Maximize Distance to Closest Person LeetCode Solution155
1098Number of Closed Islands Leetcode Solution155
1099Remove duplicates from sorted array155
1100Sum of Even Numbers After Queries154
1101Construct Binary Tree from Preorder and Postorder Traversal LeetCode Solution154
1102Print all triplets in sorted array that form AP154
1103Valid Tic-Tac-Toe State LeetCode Solution154
1104Number of siblings of a given Node in n-ary Tree154
1105Divisible Pairs Counting154
1106Path Sum154
1107Search in Sorted Rotated Array153
1108Binary Tree Data Structure153
1109Thousand Separator Leetcode Solution153
1110Iterative method to find ancestors of a given binary tree153
1111Moser-de Bruijn Sequence153
1112Reformat The String Leetcode Solution153
1113Find Three Element From Different Three Arrays Such That a + b + c = sum153
1114Find the minimum distance between two numbers153
1115Kth Smallest Product of Two Sorted Arrays LeetCode Solution152
1116Products of ranges in an array152
1117Cells with Odd Values in a Matrix LeetCode Solution152
1118Day of the Year Leetcode Solution152
1119Find Smallest Range Containing Elements from k Lists152
1120Count Largest Group Leetcode Solution152
1121Level of Each node in a Tree from source node152
1122Search Insert Position152
1123Mean of Array After Removing Some Elements Leetcode Solution152
1124Number of Students Doing Homework at a Given Time Leetcode Solution152
1125Root to Leaf path with target sum Leetcode Solutions151
1126Minimum Absolute Difference in BST Leetcode Solution151
1127Distinct Subsequences151
1128Serialize and Deserialize Binary Tree LeetCode Solution151
1129Bottom View of a Binary Tree151
1130Longest Increasing Consecutive Subsequence151
1131Clone a Binary Tree with Random Pointers151
1132Prime Palindrome LeetCode Solution150
1133Third Maximum Number Leetcode Solution150
1134Find maximum length Snake sequence150
1135Constant time range add operation on an array150
1136Maximum Product of Splitted Binary Tree LeetCode Solution150
1137Find Two Non-overlapping Sub-arrays Each With Target Sum LeetCode Solution150
1138Closest Leaf in a Binary Tree LeetCode Solution150
1139Convert BST into a Min-Heap without using array150
1140Topological Sorting150
1141Maximum Product Subarray150
1142Compare Strings by Frequency of the Smallest Character Leetcode Solution150
1143Write Code to Determine if Two Trees are Identical149
1144Minimum sum of squares of character counts in a given string after removing k characters149
1145Maximum Depth Of Binary Tree149
1146Construct K Palindrome Strings LeetCode Solution149
1147Minimum Moves to Equal Array Elements LeetCode Solution149
1148Diameter of N-Ary Tree LeetCode Solution149
1149Longest Repeated Subsequence149
1150Queries for Number of Distinct Elements in a Subarray149
1151Longest Subarray of 1’s After Deleting One Element LeetCode Solution149
1152Print modified array after executing the commands of addition and subtraction148
1153Web Crawler LeetCode Solution148
1154Golomb sequence148
1155Rotate Array148
1156Minimum Score Triangulation of Polygon Leetcode Solution148
1157Priority Queue148
1158Count even length binary sequences with same sum of first and second half bits148
1159Search an Element in Sorted Rotated Array148
1160Reformat Date LeetCode Solution148
1161Cutting a Rod147
1162Find a sorted subsequence of size 3 in linear time147
1163Swap Nodes In Pairs147
1164Subset Sum Problem in O(sum) space147
1165Find Largest Value in Each Tree Row LeetCode Solution147
1166Closest Binary Search Tree Value Leetcode Solution147
1167Delete Nodes and Return Forest Leetcode Solution147
1168Minimum Cost to Move Chips to The Same Position LeetCode Solution146
1169Kth Smallest Number in Multiplication Table Leetcode Solution146
1170Count Pairs Whose Products Exist in Array146
1171Red-Black Tree Introduction146
1172Contiguous Array LeetCode Solution146
1173Search Suggestions System LeetCode Solution146
1174Matchsticks to Square Leetcode Solution146
1175Maximize sum of consecutive differences in a circular array146
1176Given a binary tree, how do you remove all the half nodes?146
1177Maximum sum of a path in a Right Number Triangle145
1178K’th Largest element in BST using constant extra space145
1179Minimum Swaps To Make Sequences Increasing LeetCode Solution145
1180Possible Bipartition LeetCode Solution145
1181Transform a BST to Greater sum Tree145
1182Decision Tree145
1183Minimum Sideway Jumps LeetCode Solution145
1184Decrease Elements To Make Array Zigzag LeetCode Solution144
1185Remove Max Number of Edges to Keep Graph Fully Traversable Leetcode Solution144
1186Sum of Left Leaves LeetCode Solution144
1187Factorial Trailing Zeroes LeetCode Solution144
1188Find the smallest binary digit multiple of given number144
1189First Bad Version144
1190Replace two consecutive equal values with one greater144
1191Merge two BSTs with limited extra space144
1192Binary Tree to Binary Search Tree Conversion144
1193Reverse a Path in BST using Queue144
1194Path Crossing Leetcode Solution144
1195Maximum Binary Tree144
1196Maximum Value at a Given Index in a Bounded Array LeetCode Solution144
1197Check Array Formation Through Concatenation Leetcode Solution144
1198Number of Orders in the Backlog Leetcode Solution143
1199Maximum sum bitonic subarray143
1200Print n terms of Newman-Conway Sequence143
1201Convert Integer to the Sum of Two No-Zero Integers Leetcode Solution143
1202Valid Triangle Number143
1203Maximum sum of pairs with specific difference143
1204Perfect Squares LeetCode Solution143
1205Concatenation of Array LeetCode Solution143
1206Maximum number of segments of lengths a, b and c143
1207Sliding Window Median Leetcode Solution142
1208Divide Two Integers Leetcode Solution142
1209Queue Reconstruction by Height142
1210Convert Sorted Array to Binary Search Tree LeetCode Solutions142
1211Queries on Probability of Even or Odd Number in given Ranges142
1212Valid Perfect Square LeetCode Solution142
1213Swapping Nodes in a Linked List Leetcode Solution142
1214Guess The Word141
1215New 21 Game141
1216How to print maximum number of A’s using given four keys141
1217Integer Break LeetCode Solution141
1218Graph and its representation140
1219Lowest Common Ancestor in Binary Search Tree140
1220Lowest Common Ancestor of a Binary Tree Leetcode Solution140
1221Array Queries for multiply replacements and product140
1222Champagne Tower LeetCode Solution140
1223Kth Smallest Element in a BST140
1224Moving Stones Until Consecutive Leetcode Solution139
1225Check if all levels of two Binary Tree are anagrams or not139
1226Find minimum number of merge operations to make an array palindrome139
1227Merge k Sorted Lists Leetcode Solution139
1228Maximum Array from Two given Arrays Keeping Order Same139
1229Longest Common Prefix Using Word by Word Matching139
1230Flatten 2D Vector LeetCode Solution139
1231Filter Restaurants by Vegan-Friendly, Price and Distance Leetcode Solution138
1232Mean of range in array138
1233Find Minimum in Rotated Sorted Array II LeetCode Solution138
1234Design Skiplist LeetCode Solution138
1235Write a function to get the intersection point of two Linked Lists138
1236Contiguous Array138
1237Range Sum Query using Sparse Table138
1238Missing Number137
1239Bold Words in String LeetCode Solution137
1240LRU Cache Leetcode Solution137
1241BST to a Tree with Sum of all Smaller Keys137
1242Maximum Sum Increasing Subsequence137
1243Maximize Elements Using Another Array137
1244Range Queries for Longest Correct Bracket Subsequence137
1245Print modified array after multiple array range increment operations137
1246The kth Factor of n Leetcode Solution136
1247Find k-th smallest element in BST (Order Statistics in BST)136
1248Maximum Product Subarray136
1249Largest Plus Sign Leetcode Solution136
1250Min Cost Climbing Stairs LeetCode Solution136
1251Minimum Remove to Make Valid Parentheses LeetCode Solution136
1252Parallel Courses II LeetCode Solution136
1253Count Subsets Having Distinct Even Numbers136
1254Power of Two135
1255Graph Cloning135
1256Check in binary array the number represented by a subarray is odd or even135
1257Arithmetic Slices II – Subsequence LeetCode Solution134
1258Different Ways to Add Parentheses Leetcode Solution134
1259Minimum Time to Collect All Apples in a Tree LeetCode Solution134
1260Check if each internal node of a BST has exactly one child134
1261Image Overlap LeetCode Solution134
1262Verify Preorder Serialization of a Binary Tree134
1263Check for Identical BSTs without building the trees133
1264Check if two nodes are on the same path in a Tree133
1265Orderly Queue LeetCode Solution132
1266Print Ancestors of a Given Binary Tree Node Without Recursion132
1267Koko Eating Bananas LeetCode Solution132
1268Symmetric Tree LeetCode Solution Leetcode Solution132
1269Check Completeness of a Binary Tree LeetCode Solution132
1270Longest Substring Without Repeating Characters Leetcode Solution132
1271Smallest Range II Leetcode Solution132
1272Excel Sheet Column Title LeetCode Solution131
1273Next greater element131
1274Arranging Coins Leetcode Solution130
1275Vertical Order Traversal of Binary Tree LeetCode Solution129
1276Number of elements less than or equal to a given number in a given subarray129
1277Count and Toggle Queries on a Binary Array129
1278Merge Sorted Array129
1279Largest Submatrix With Rearrangements LeetCode Solution128
1280Array Nesting Leetcode Solution127
1281Palindrome Partitioning127
1282Palindrome Number LeetCode Solution127
1283Peeking Iterator LeetCode Solution126
1284Add Two Numbers II Leetcode Solution126
1285Newman–Shanks–Williams prime126
1286Check If a String Can Break Another String Leetcode Solution126
1287Queries for Decimal Values of Subarrays of a Binary Array125
1288Range Minimum Query (Square Root Decomposition and Sparse Table)125
1289Find the Winner of the Circular Game LeetCode Solution125
1290Maximum product of an increasing subsequence125
1291Insert Delete GetRandom O(1) Leetcode Solution125
1292Check if X can give change to every person in the Queue125
1293Find maximum average subarray of k length124
1294Encoded String With Shortest Length LeetCode Solution123
1295Check given array of size n can represent BST of n levels or not123
1296Number of Subsequences That Satisfy the Given Sum Condition LeetCode solution123
1297Continuous Subarray Sum LeetCode Solution121
1298Jump Game IV LeetCode Solution121
1299Random Pick Index LeetCode Solution121
1300Minimum Possible Integer After at Most K Adjacent Swaps On Digits LeetCode Solution120
1301Minimum Number of People to Teach LeetCode Solution120
1302Number of indexes with equal elements in given range120
1303Reach a Number LeetCode Solution120
1304Binary Tree to Binary Search Tree Conversion using STL set120
1305Convert a BST to a Binary Tree such that sum of all greater keys is added to every key118
1306Minimum Total Space Wasted With K Resizing Operations LeetCode Solution117
1307Convert to Base -2 LeetCode Solution116
1308Design A Leaderboard Leetcode Solution115
1309Queries on XOR of greatest odd divisor of the range115
1310Design Underground System Leetcode Solution114
1311Shifting Letters LeetCode Solution112
1312Print Maximum Length Chain of Pairs111
1313Detect Capital Leetcode Solution111
1314Top K Frequent Elements LeetCode Solution110
1315Minimum Swaps to Group All 1’s Together Leetcode Solution110
1316Count Sub Islands LeetCode Solution108
1317Minimum Path Sum Leetcode Solution108
1318Substring with Concatenation of All Words Leetcode Solution107
1319Odd Even Linked List Leetcode Solution106
1320Monotonic Array Leetcode Solution105
1321Longest Common Subsequence LeetCode Solution102
1322Binary Tree Inorder Traversal LeetCode Solution101
1323Decode String Leetcode Solution101
1324Find the Town Judge LeetCode Solution100
1325Maximum Population Year LeetCode Solution100
1326Shortest Unsorted Continuous Subarray LeetCode Solution96
1327Rectangle Overlap LeetCode Solution95
1328Best Meeting Point LeetCode Solution94
1329Maximum Population Year LeetCode Solution93
1330Find the Town Judge LeetCode Solution92
1331Flatten Binary Tree to Linked List LeetCode Solution91
1332Insert into a Sorted Circular Linked List LeetCode Solution91
1333Sum Root to Leaf Numbers LeetCode Solution91
1334Design Add and Search Words Data Structure LeetCode Solution90
1335Reveal Cards In Increasing Order Leetcode Solution88
1336Stone Game IV LeetCode Solution88
1337Is Graph Bipartite? LeetCode Solution87
1338Range Sum Query 2D – Immutable LeetCode Solution87
1339Valid Triangle Number LeetCode Solution86
1340Score of Parenthesis LeetCode Solution85
1341Divide Chocolate LeetCode Solution81
1342Step-By-Step Directions From a Binary Tree Node to Another LeetCode Solution76
1343Range Sum of BST LeetCode Solution70
1344Reverse Integer Leetcode Solution67
1345Rotate String LeetCode Solution64
1346Find K Closest Elements LeetCode Solution64
1347Sort Colors LeetCode Solution63
1348Maximum Side Length of a Square with Sum Less than or Equal to Threshold LeetCode Solution61
1349Excel Sheet Column Number LeetCode Solution57
1350Maximum Size Subarray Sum Equals k Leetcode Solution50
1351H-Index Leetcode Solution46
1352Camelcase Matching Leetcode Solution45
1353Valid Anagram Leetcode Solution44
1354Most Stones Removed with Same Row or Column LeetCode Solution43
1355Container With Most Water LeetCode Solution43
1356Sliding Window Maximum LeetCode Solution42
1357High Five LeetCode Solution42
1358Group Anagrams LeetCode Solution42
1359Next Permutation LeetCode Solution41
1360Binary Search LeetCode Solution40
1361Find Peak Element LeetCode Solution40
1362Pairs of Songs With Total Durations Divisible by 60 LeetCode Solution39
1363Paint House LeetCode Solution37
1364Minimum Number of Arrows to Burst Balloons LeetCode Solution36
1365Valid Triangle Number LeetCode Solution36
1366Flatten Binary Tree to Linked List LeetCode Solution35
1367Isomorphic Strings LeetCode Solution35
1368Unique Binary Search Trees LeetCode Solution35
1369Next Greater Element I Leetcode Solution35
1370Sentence Screen Fitting LeetCode Solution34
1371Group Shifted Strings Leetcode Solution34
1372Count Good Nodes in Binary Tree LeetCode Solution34
1373The Number of Weak Characters in the Game LeetCode Solution34
1374Swim in Rising Water LeetCode Solution32
1375Insert Delete GetRandom O(1) – Duplicates allowed LeetCode Solution32
1376Single Element in a Sorted Array LeetCode Solution31
1377Closest Binary Search Tree Value II LeetCode Solution31
1378Peak Index in a Mountain Array LeetCode Solution31
1379Split Linked List in Parts Leetcode Solution30
1380Find First and Last Position of Element in Sorted Array LeetCode Solution28
1381Lowest Common Ancestor of a Binary Search Tree Leetcode Solution27
1382Max Sum of Two Non-Overlapping Subarrays LeetCode Solution27
1383All Possible Full Binary Trees LeetCode Solution27
1384Best Time to Buy and Sell Stock IV LeetCode Solution27
1385Validate Stack Sequences LeetCode Solution26
1386Minimum Increment to Make Array Unique Leetcode Solution26
1387Detect Squares LeetCode Solution25
1388Implement strStr() LeetCode Solution25
1389Implement Rand10() Using Rand7() Leetcode Solution24
1390Trapping Rain Water II LeetCode Solution24
1391Break a Palindrome LeetCode Solution24
1392Greatest Sum Divisible by Three LeetCode Solution24
1393Stone Game IV LeetCode Solution22
1394Invert Binary Tree LeetCode Solution22
1395Remove All Ones With Row and Column Flips Leetcode Solution22
1396Contains Duplicate LeetCode Solution22
1397Fibonacci Number LeetCode Solution20
1398Reverse Nodes in k-Group LeetCode Solution20
1399Minimum Number of Operations to Move All Balls to Each Box LeetCode Solution20
1400Design Bounded Blocking Queue LeetCode Solution19
1401Total Hamming Distance LeetCode Solution16
1402Candy LeetCode Solution16
1403Unique Paths III LeetCode Solution14
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