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274 problems

Title Topic Difficulty Platform
3Sum Array Medium LeetCode
3Sum Closest Array Medium LeetCode
4Sum Array Medium LeetCode
Add Binary Matrix Easy LeetCode
Add Two Numbers Linked-List Medium LeetCode
Add Two Numbers II Linked-List Medium LeetCode
alien-dictionary Graph Hard Other
All Nodes Distance K in Binary Tree Tree Medium LeetCode
Allocate Minimum Pages | Practice Sorting&Searching Hard GeeksforGeeks
As Far from Land as Possible Graph Medium LeetCode
Backspace String Compare Stack&Queue Easy LeetCode
Balanced Binary Tree Tree Easy LeetCode
Basic Calculator II String Medium LeetCode
Beautiful Arrangement Backtracking Medium LeetCode
Best Time to Buy and Sell Stock Array Easy LeetCode
Best Time to Buy and Sell Stock II Array Easy LeetCode
Best Time to Buy and Sell Stock IV Dynamic-Programming Hard LeetCode
BFS of graph | Practice Graph Easy GeeksforGeeks
Binary Search Tree Iterator Tree Medium LeetCode
Binary Tree Cameras Tree Hard LeetCode
Binary Tree Level Order Traversal Daily Tree Medium LeetCode
Binary Tree Maximum Path Sum Tree Hard LeetCode
Binary Tree Paths Tree Easy LeetCode
Binary Tree Right Side View Tree Medium LeetCode
Binary Tree Zigzag Level Order Traversal Tree Medium LeetCode
Boyer Moore Algorithm for Pattern Searching String Hard GeeksforGeeks
BST with Dead End | Practice Tree Easy GeeksforGeeks
Burst Balloons Dynamic-Programming Hard LeetCode
Ceiling in a sorted array Sorting&Searching Easy GeeksforGeeks
Cheapest Flights Within K Stops Graph Medium LeetCode
Check if it is possible to finish all task from given dependencies (Course Schedule I) Graph Medium GeeksforGeeks
Check if reversing a sub array make the array sorted Sorting&Searching Medium GeeksforGeeks
Check whether a given graph is Bipartite or not Graph Medium GeeksforGeeks
Chocolate Distribution Problem Array Easy GeeksforGeeks
Climbing Stairs Dynamic-Programming Easy LeetCode
Coin Change Dynamic-Programming Medium LeetCode
Combinations Backtracking Medium LeetCode
Construct Binary Tree from Preorder and Postorder Traversal Tree Medium LeetCode
Construct BST from Preorder Traversal Tree Hard GeeksforGeeks
Container With Most Water Array Medium LeetCode
Convert Binary Number in a Linked List to Integer Linked-List Easy LeetCode
Convert Sorted Array to Binary Search Tree Tree Easy LeetCode
Copy List with Random Pointer Linked-List Medium LeetCode
Count BST nodes that lie in a given range | Practice Tree Medium GeeksforGeeks
Count Different Palindromic Subsequences Dynamic-Programming Hard LeetCode
Count of Smaller Numbers After Self Sorting&Searching Hard LeetCode
Count Square Submatrices with All Ones Dynamic-Programming Medium LeetCode
Counting Bits Dynamic-Programming Easy LeetCode
Critical Connections in a Network Graph Hard LeetCode
Daily Temperatures Stack&Queue Medium LeetCode
Decode String Graph Medium LeetCode
Decode Ways Dynamic-Programming Medium LeetCode
Delete and Earn Dynamic-Programming Medium LeetCode
Depth First Search or DFS for a Graph Graph Easy GeeksforGeeks
Design Add and Search Words Data Structure Tries Medium LeetCode
Detect a negative cycle in a Graph | (Bellman Ford) Graph Medium GeeksforGeeks
Detect Cycle in a Directed Graph Graph Easy GeeksforGeeks
Diameter of Binary Tree Tree Easy LeetCode
Distance of nearest cell having 1 | Practice Stack&Queue Medium GeeksforGeeks
Distinct Subsequences String Hard LeetCode
Evaluate Division Graph Medium LeetCode
Evaluate Reverse Polish Notation Stack&Queue Medium LeetCode
Evaluation of Postfix Expression Stack&Queue Easy GeeksforGeeks
Excel Sheet Column Title Matrix Easy LeetCode
Find All Duplicates in an Array Array Medium LeetCode
Find Eventual Safe States Graph Medium LeetCode
Find Maximum number possible by doing at-most K swaps Backtracking Hard GeeksforGeeks
Find median of BST Tree Hard GeeksforGeeks
Find paths from corner cell to middle cell in maze Backtracking Hard GeeksforGeeks
Find Peak Element Sorting&Searching Medium LeetCode
Find the City With the Smallest Number of Neighbors at a Threshold Distance Graph Medium LeetCode
Find the Duplicate Number Array Easy LeetCode
Find the Index of the First Occurrence in a String String Easy LeetCode
Flatten a Multilevel Doubly Linked List Linked-List Medium LeetCode
Flatten Binary Tree to Linked List Tree Medium LeetCode
Flatten Nested List Iterator Stack&Queue Medium LeetCode
Flattening a Linked List Linked-List Hard GeeksforGeeks
Flood Fill Graph Easy LeetCode
Floyd Warshall | Practice Graph Medium GeeksforGeeks
Frog Jump Dynamic-Programming Hard LeetCode
Game of Life Array Medium LeetCode
Gas Station | Practice Stack&Queue Medium GeeksforGeeks
Generate Parentheses String Medium LeetCode
Given a matrix of ‘O’ and ‘X’, replace ‘O’ with ‘X’ if surrounded by ‘X’ Matrix Medium GeeksforGeeks
Given only a pointer/reference to a node to be deleted in a singly linked list, how do you delete it? Linked-List Easy GeeksforGeeks
Happy Number Matrix Easy LeetCode
https://leetcode.com/problems/binary-tree-inorder-traversal/ Tree Easy LeetCode
https://leetcode.com/problems/implement-stack-using-queues Stack&Queue Medium LeetCode
https://practice.geeksforgeeks.org/problems/binary-tree-to-dll/1 Tree Hard GeeksforGeeks
Implement Queue using Stacks Stack&Queue Easy LeetCode
Implement Stack and Queue using Deque Stack&Queue Easy GeeksforGeeks
Implement Stack using Queues Stack&Queue Easy LeetCode
Implement two Stacks in an Array Stack&Queue Easy GeeksforGeeks
Insert Delete GetRandom O(1) - Duplicates allowed Array Hard LeetCode
Integer to English Words String Hard LeetCode
Integer to Roman String Medium LeetCode
Intersection of Two Linked Lists Linked-List Easy LeetCode
Introduction to Graph Coloring Graph Medium GeeksforGeeks
Invert Binary Tree Tree Easy LeetCode
Jump Game Array Medium LeetCode
K-th Symbol in Grammar Backtracking Medium LeetCode
Knight Dialer Dynamic-Programming Medium LeetCode
Kth Smallest Element in a BST Tree Medium LeetCode
Largest area rectangular sub-matrix with equal number of 1’s and 0’s Dynamic-Programming Hard GeeksforGeeks
Largest BST in a Binary Tree Tree Hard GeeksforGeeks
Largest Rectangle in Histogram Array Hard LeetCode
Letter Combinations of a Phone Number Stack&Queue Medium LeetCode
Linked List Cycle Linked-List Easy LeetCode
Longest Common Prefix String Easy LeetCode
Longest Common Substring | Practice Dynamic-Programming Medium GeeksforGeeks
Longest Happy Prefix String Hard LeetCode
Longest Increasing Path in a Matrix Graph Hard LeetCode
Longest Increasing Subsequence Dynamic-Programming Medium LeetCode
Longest Repeating Character Replacement Two-Pointer Medium LeetCode
Lowest Common Ancestor of a Binary Search Tree Tree Easy LeetCode
Lowest Common Ancestor of a Binary Tree Tree Medium LeetCode
LRU Cache – Complete Tutorial Stack&Queue Hard GeeksforGeeks
M-Coloring Problem | Practice Backtracking Medium GeeksforGeeks
Majority Element Array Easy LeetCode
Make all array elements equal with minimum cost Sorting&Searching Medium GeeksforGeeks
Making A Large Island Graph Hard LeetCode
Max Points on a Line Matrix Medium LeetCode
Max Value of Equation Array Hard LeetCode
Maximal Rectangle Dynamic-Programming Hard LeetCode
Maximal Square Dynamic-Programming Medium LeetCode
Maximize The Cut Segments | Practice Dynamic-Programming Medium GeeksforGeeks
Maximum Depth of Binary Tree Tree Easy LeetCode
Maximum Length of Repeated Subarray Dynamic-Programming Medium LeetCode
Maximum Number of Visible Points Two-Pointer Medium LeetCode
Maximum of minimums of every window size in a given array Stack&Queue Hard GeeksforGeeks
Maximum Points You Can Obtain from Cards Array Medium LeetCode
Maximum Product of Three Numbers Matrix Easy LeetCode
Maximum Product Subarray Dynamic-Programming Easy LeetCode
Maximum size rectangle binary sub-matrix with all 1s Matrix Medium GeeksforGeeks
Maximum Width of Binary Tree Tree Medium LeetCode
Merge k Sorted Lists Linked-List Hard LeetCode
Merge Sort for Linked Lists Linked-List Hard GeeksforGeeks
Merge Sorted Array Array Easy LeetCode
Merge Two Binary Trees Tree Easy LeetCode
Merge Two Sorted Lists Linked-List Easy LeetCode
Middle of the Linked List Linked-List Easy LeetCode
Min distance between two given nodes of a Binary Tree | Practice Tree Medium GeeksforGeeks
Minimize Cash Flow among a given set of friends who have borrowed money from each other Graph Hard GeeksforGeeks
Minimum Absolute Difference in BST Tree Easy LeetCode
Minimum Cost to Hire K Workers Heap Hard LeetCode
Minimum Cost to Merge Stones Dynamic-Programming Hard LeetCode
Minimum Cost Tree From Leaf Values Stack&Queue Medium LeetCode
Minimum Insertion Steps to Make a String Palindrome Dynamic-Programming Hard LeetCode
Minimum Moves to Equal Array Elements Matrix Easy LeetCode
Minimum Number of Refueling Stops Heap Hard LeetCode
Minimum Path Sum Dynamic-Programming Medium LeetCode
Minimum swaps to sort an array Sorting&Searching Hard GeeksforGeeks
Minimum Window Substring String Hard LeetCode
Missing Number Matrix Easy LeetCode
Mobile numeric keypad | Practice Dynamic-Programming Medium GeeksforGeeks
Most Stones Removed with Same Row or Column Graph Medium LeetCode
Move Zeroes Array Easy LeetCode
Multiply two numbers represented by Linked Lists Linked-List Easy GeeksforGeeks
N-Queens Backtracking Hard LeetCode
Next Greater Element I Stack&Queue Easy LeetCode
Number of Islands Matrix Medium GeeksforGeeks
Number of Islands Daily Graph Easy LeetCode
Number of Operations to Make Network Connected Graph Medium LeetCode
Ones and Zeroes Dynamic-Programming Easy LeetCode
Online Stock Span Stack&Queue Medium LeetCode
Optimal Binary Search Tree Dynamic-Programming Hard GeeksforGeeks
Pair with the given difference Sorting&Searching Easy GeeksforGeeks
Palindrome Linked List Linked-List Easy LeetCode
Palindrome Number Matrix Easy LeetCode
Palindrome Pairs Tries Hard LeetCode
Palindrome Partitioning Backtracking Medium LeetCode
Partition List Linked-List Medium LeetCode
Partition of a set into K subsets with equal sum Backtracking Hard GeeksforGeeks
Path Sum Tree Easy LeetCode
Path Sum III Tree Medium LeetCode
Permutations II Backtracking Medium LeetCode
Permute two arrays such that sum of every pair is greater or equal to K Sorting&Searching Easy GeeksforGeeks
Permute two arrays such that sum of every pair is greater or equal to K Sorting&Searching Easy GeeksforGeeks
phone-directory Tries Hard Other
Populating Next Right Pointers in Each Node Tree Medium LeetCode
Power of Two Matrix Easy LeetCode
Predecessor and Successor | Practice Tree Easy GeeksforGeeks
Preorder to BST | Practice Tree Medium GeeksforGeeks
Prim’s Algorithm for Minimum Spanning Tree (MST) Graph Medium GeeksforGeeks
Print all combinations | Set-2 Array Medium GeeksforGeeks
Print all k-sum paths in a binary tree Tree Hard GeeksforGeeks
Print all Palindromic Partitions of a String using Bit Manipulation Backtracking Hard GeeksforGeeks
Print all the duplicate characters in a string String Easy GeeksforGeeks
Print Anagrams Together | Practice Tries Medium GeeksforGeeks
Product of Array Except Self Sorting&Searching Medium GeeksforGeeks
Radix Sort – Data Structures and Algorithms Tutorials Sorting&Searching Medium GeeksforGeeks
Range Sum of BST Tree Easy LeetCode
Range Sum Query 2D - Immutable Dynamic-Programming Medium LeetCode
Rat in a Maze Problem - I | Practice Graph Easy GeeksforGeeks
Rearrange a given linked list in-place Linked-List Medium GeeksforGeeks
Rearrange a Linked List in Zig-Zag fashion Linked-List Medium GeeksforGeeks
Recover Binary Search Tree Tree Medium LeetCode
Redundant Connection Tree Medium LeetCode
Remove Boxes Graph Hard LeetCode
Remove Duplicates from Sorted Array Array Easy LeetCode
Remove Duplicates from Sorted List Linked-List Easy LeetCode
Remove Duplicates from Sorted List II Linked-List Medium LeetCode
Remove Linked List Elements Linked-List Easy LeetCode
Remove Nth Node From End of List Linked-List Medium LeetCode
Reorder List Linked-List Medium LeetCode
Reverse Integer Matrix Easy LeetCode
Reverse Linked List Linked-List Easy LeetCode
Reverse Linked List II Linked-List Medium LeetCode
Reverse Nodes in k-Group Linked-List Hard LeetCode
Reverse Pairs Array Hard LeetCode
Reverse Words in a String String Medium LeetCode
Rotate Image Matrix Medium LeetCode
Rotten Oranges | Practice Stack&Queue Medium GeeksforGeeks
Same Tree Tree Easy LeetCode
Search in Rotated Sorted Array Sorting&Searching Hard LeetCode
Segregate even and odd nodes in a Linked List Linked-List Medium GeeksforGeeks
Serialize and Deserialize Binary Tree Tree Hard LeetCode
Set Matrix Zeroes Array Easy LeetCode
Shortest Bridge Graph Medium LeetCode
Simplify Path String Medium LeetCode
Sliding Window Maximum Heap Hard LeetCode
Snakes and Ladders Graph Medium LeetCode
Solving Cryptarithmetic Puzzles Backtracking Hard GeeksforGeeks
Sort a linked list of 0s, 1s and 2s Linked-List Easy GeeksforGeeks
Sort Colors Array Easy LeetCode
Sort Colors Two-Pointer Medium LeetCode
Sort List Linked-List Medium LeetCode
Spiral Matrix Array Medium LeetCode
Spiral Matrix Matrix Medium LeetCode
Split Array Largest Sum Sorting&Searching Hard LeetCode
SPOJ.com - Problem AGGRCOW Sorting&Searching Hard Other
Steps by Knight | Practice Graph Medium GeeksforGeeks
Strongly Connected | Practice Graph Medium GeeksforGeeks
Subarray Sum Equals K Array Medium LeetCode
Subarray Sums Divisible by K Array Medium LeetCode
Subset Sum Problem Backtracking Medium GeeksforGeeks
Subsets II Backtracking Medium LeetCode
Subtract Two Numbers represented as Linked Lists Linked-List Hard GeeksforGeeks
Subtree of Another Tree Tree Easy LeetCode
Sudoku Solver Backtracking Hard LeetCode
Sum of Distances in Tree Tree Hard LeetCode
Sum of Left Leaves Tree Easy LeetCode
Sum of Subarray Minimums Stack&Queue Medium LeetCode
Super Egg Drop Dynamic-Programming Hard LeetCode
Swim in Rising Water Heap Hard LeetCode
Symmetric Tree Tree Easy LeetCode
Text Justification String Hard LeetCode
The Celebrity Problem Stack&Queue Hard GeeksforGeeks
The kth Factor of n Matrix Medium LeetCode
Time Needed to Inform All Employees Graph Medium LeetCode
Topological sort | Practice Graph Medium GeeksforGeeks
Total number of Spanning Trees in a Graph Graph Hard GeeksforGeeks
Trapping Rain Water Dynamic-Programming Hard LeetCode
Travelling Salesman Problem using Dynamic Programming Graph Hard GeeksforGeeks
Trie Data Structure Tries Medium GeeksforGeeks
Tug of War Backtracking Hard GeeksforGeeks
Two Sum Daily Array Easy LeetCode
Undirected Graph Cycle | Practice Graph Easy GeeksforGeeks
Unique Binary Search Trees Tree Medium LeetCode
Unique Binary Search Trees II Tree Medium LeetCode
Unique Paths Dynamic-Programming Medium LeetCode
Unique Paths III Backtracking Hard LeetCode
Valid Number String Hard LeetCode
Valid Palindrome II String Easy LeetCode
Valid Parentheses Daily String Easy LeetCode
Valid Square Matrix Medium LeetCode
Validate Binary Search Tree Tree Medium LeetCode
Vertical Order Traversal of a Binary Tree Tree Hard LeetCode
Water Jug problem using BFS Graph Hard GeeksforGeeks
Weighted Job Scheduling Dynamic-Programming Medium GeeksforGeeks
Word Break Problem | (Trie solution) Tries Medium GeeksforGeeks
Word Ladder Graph Hard LeetCode
Word Search Array Medium LeetCode
Word Search II Backtracking Hard LeetCode