Featured Lists Top 20 Problems on Dynamic programming Top 10 Problems on Backtracking Top 20 Problems on Graph Top 25 Problems on Trees Top 10 Problems on Bits Manipulation Top 15 Problems in LinkedList All Problems # Status Problem video Level Completes Likes 153 Find the Second Largest Element in an Array Beginner % 1 152 Breadth-First Search/Traversal in a Graph Beginner % 1 146 Dynamic Programming - Stairs Climbing Puzzle Beginner % 1 145 Dynamic Programming - Minimum Coin Change Problem Medium % 1 144 Introduction To Dynamic Programming - Fibonacci Series Beginner % 1 141 Find the Single Occurrence Element in an Array (Odd One Out) Beginner % 1 139 Find Missing Numbers in Sequences - XOR Method Beginner % 1 136 Verifying Mirror Binary Trees Beginner % 1 134 Diameter Of a Binary Tree Hard % 1 132 Find the Deepest Node in a Binary Tree Medium % 1 121 Print All the Subsets of a Given Set (Power Set) Hard % 1 119 Clock Angle Problem Beginner % 1 117 Stack with Max Tracking: Find the Largest Element (Optimized) Medium % 1 116 Generate All Balanced Parentheses Combinations (N Pairs) Medium % 1 112 Generate All n-Bit Binary Strings Medium % 1 111 Find Unique Number in Array with Duplicates (Except One) Beginner % 1 69 Convert Sorted Singly Linked List to Balanced Binary Search Tree Medium % 1 66 Convert a Sorted Doubly Linked List to Balanced BST Medium % 1 48 Determining Whether a Given Binary Tree is a Binary Search Tree (BST) Medium % 1 41 Sorted Array to Binary Search Tree of Minimal Height Medium % 1 36 Find the Maximum Depth OR Height of a Binary Tree Beginner % 1 33 Reverse the binary representation of a number. Medium % 1 26 Check if one string is Rotation of another string Beginner % 1 23 Find Whether Two Strings are Permutation of each other Beginner % 1 19 Exploring All Paths, Including Diagonal, from Top Left to Bottom Right in 2D Array Medium % 1 2 Merge Sort - Updated - Most Efficient ways to Implement Medium % 1 555 Move All Zeroes to the End of the Array Beginner % 0 554 Counting bits - Leetcode Beginner % 0 553 Minimize Scheduling Headaches: Clone Yourself for Overlapping Events Hard % 0 552 Stock Single Sell Problem - Divide and Conquer Medium % 0 551 Reverse a linked list using stack Medium % 0 549 Dynamic Programming - Minimum Cost for Climbing Stairs Medium % 0 546 Converting to Non-Decreasing Array with One Change Medium % 0 533 In an array, Duplicate the zeroes without expanding it Beginner % 0 532 Maximum Depth of Valid Nested Parentheses in an arithmetic expression Medium % 0 Find the Second Largest Element in an Array Breadth-First Search/Traversal in a Graph Dynamic Programming - Stairs Climbing Puzzle Dynamic Programming - Minimum Coin Change Problem Introduction To Dynamic Programming - Fibonacci Series Find the Single Occurrence Element in an Array (Odd One Out) Find Missing Numbers in Sequences - XOR Method Verifying Mirror Binary Trees Diameter Of a Binary Tree Find the Deepest Node in a Binary Tree Print All the Subsets of a Given Set (Power Set) Clock Angle Problem Stack with Max Tracking: Find the Largest Element (Optimized) Generate All Balanced Parentheses Combinations (N Pairs) Generate All n-Bit Binary Strings Find Unique Number in Array with Duplicates (Except One) Convert Sorted Singly Linked List to Balanced Binary Search Tree Convert a Sorted Doubly Linked List to Balanced BST Determining Whether a Given Binary Tree is a Binary Search Tree (BST) Sorted Array to Binary Search Tree of Minimal Height Find the Maximum Depth OR Height of a Binary Tree Reverse the binary representation of a number. Check if one string is Rotation of another string Find Whether Two Strings are Permutation of each other Exploring All Paths, Including Diagonal, from Top Left to Bottom Right in 2D Array Merge Sort - Updated - Most Efficient ways to Implement Move All Zeroes to the End of the Array Counting bits - Leetcode Minimize Scheduling Headaches: Clone Yourself for Overlapping Events Stock Single Sell Problem - Divide and Conquer Reverse a linked list using stack Dynamic Programming - Minimum Cost for Climbing Stairs Converting to Non-Decreasing Array with One Change In an array, Duplicate the zeroes without expanding it Maximum Depth of Valid Nested Parentheses in an arithmetic expression 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16