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 132 Find the Deepest Node in a Binary Tree Medium % 1 131 Find the Height of a tree without using Recursion Medium % 0 130 Find and Print Full Nodes in a Binary Tree Beginner % 0 129 Binary Min-Max Heap Implementation Hard % 0 128 Magic Index - Find Index In Sorted Array Such That A[i] = i Beginner % 0 127 Numbers Palindrome in Both Decimal and Octal Beginner % 0 126 Generate All Permutations of a String (Well-Ordered) Medium % 0 125 Find the Increasing Triplet Sub-sequence in an array Medium % 0 124 Create a Specific Triangle Pattern from an Array Beginner % 0 123 Colorful Numbers Hard % 3 122 Goldbach's Conjecture Beginner % 0 121 Print All the Subsets of a Given Set (Power Set) Hard % 1 120 Convert Decimal to Irreducible Fraction (Simplified Form) Beginner % 0 119 Clock Angle Problem Beginner % 1 118 Print All Combinations of subset of size K from Given Array Hard % 0 117 Stack with Max Tracking: Find the Largest Element (Optimized) Medium % 1 116 Generate All Balanced Parentheses Combinations (N Pairs) Medium % 1 115 Graph Representation - Adjacency Matrix and Adjacency List Beginner % 2 114 Counting Sort Algorithm Medium % 0 113 Towers Of Hanoi Beginner % 0 112 Generate All n-Bit Binary Strings Medium % 1 111 Find Unique Number in Array with Duplicates (Except One) Beginner % 1 110 Tricky Sorting: Sort 3 Numbers Without If Statements (or Only Max()) Beginner % 0 109 Find Greatest Common Divisor (GCD) Efficiently with Euclidean Algorithm Beginner % 0 108 Queue with Stacks: Efficient Implementation Using Stack Operations Medium % 0 107 Alternate Splitting of a given Linked List Medium % 0 106 Reverse a Doubly-Linked List (In-place Algorithm) Medium % 0 105 Swapping Nodes in a Linked List (Kth Position) Medium % 0 104 Print the Bottom View of a Binary Tree Medium % 0 103 Delete X Nodes After Y Nodes In a Linked List Beginner % 0 102 Merge Sort for Linked Lists (In-place Algorithm) Medium % 0 101 Merge a Linked list into another Linked List at Alternate Positions Medium % 0 100 AVL Tree - Insertion Hard % 0 99 Construct a binary tree from given Inorder and Level Order Traversal Hard % 0 98 Construct Binary Search Tree from a given Preorder Traversal Using Stack (Without Recursion) Hard % 0 Find the Deepest Node in a Binary Tree Find the Height of a tree without using Recursion Find and Print Full Nodes in a Binary Tree Binary Min-Max Heap Implementation Magic Index - Find Index In Sorted Array Such That A[i] = i Numbers Palindrome in Both Decimal and Octal Generate All Permutations of a String (Well-Ordered) Find the Increasing Triplet Sub-sequence in an array Create a Specific Triangle Pattern from an Array Colorful Numbers Goldbach's Conjecture Print All the Subsets of a Given Set (Power Set) Convert Decimal to Irreducible Fraction (Simplified Form) Clock Angle Problem Print All Combinations of subset of size K from Given Array Stack with Max Tracking: Find the Largest Element (Optimized) Generate All Balanced Parentheses Combinations (N Pairs) Graph Representation - Adjacency Matrix and Adjacency List Counting Sort Algorithm Towers Of Hanoi Generate All n-Bit Binary Strings Find Unique Number in Array with Duplicates (Except One) Tricky Sorting: Sort 3 Numbers Without If Statements (or Only Max()) Find Greatest Common Divisor (GCD) Efficiently with Euclidean Algorithm Queue with Stacks: Efficient Implementation Using Stack Operations Alternate Splitting of a given Linked List Reverse a Doubly-Linked List (In-place Algorithm) Swapping Nodes in a Linked List (Kth Position) Print the Bottom View of a Binary Tree Delete X Nodes After Y Nodes In a Linked List Merge Sort for Linked Lists (In-place Algorithm) Merge a Linked list into another Linked List at Alternate Positions AVL Tree - Insertion Construct a binary tree from given Inorder and Level Order Traversal Construct Binary Search Tree from a given Preorder Traversal Using Stack (Without Recursion) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16