Alone in couple (Solution) |
Reverse array in groups (Solution) |
Check if string is rotated by two places (Solution) |

Binary Search (Solution) |
Power of 2 (Solution) |
Permutations of a given string (Solution) |

Missing number in array (Solution) |
Number of paths (Solution) |
Count total set bits (Solution) |

Number is sparse or not (Solution) |
Bit Difference (Solution) |
Leaders in an array (Solution) |

Longest Consecutive 1’s (Solution) |
Minimize the sum of product (Solution) |
Chocolate Distribution Problem (Solution) |

Check if two arrays are equal or not (Solution) |
Find first set bit (Solution) |
Find first repeated character (Solution) |

Last index of One (Solution) |
First element to occur k times (Solution) |
Uncommon characters (Solution) |

Rotate Bits (Solution) |
Rightmost different bit (Solution) |
Set kth bit (Solution) |

Toggle bits given range (Solution) |
Longest Common Prefix in an Array (Solution) |
Count Leaves in Binary Tree (Solution) |

Merge Sort (Solution) |
Height of Binary Tree (Solution) |
Finding middle element in a linked list (Solution) |

Implement Stack using Linked List (Solution) |
Implement Queue using Linked List (Solution) |
Implement Atoi (Solution) |

Count distinct elements in every window (Solution) |
Anagram (Solution) |
Parenthesis Checker (Solution) |

Maximize Toys (Solution) |
Minimum number of Coins (Solution) |
Reverse words in a given string (Solution) |

Pythagorean Triplet (Solution) |
Activity Selection (Solution) |
Spirally traversing a matrix (Solution) |

Sort an array of 0s, 1s and 2s (Solution) |
Subset Sum Problem (Solution) |
Stock buy and sell (Solution) |

Longest Distinct characters in string (Solution) |
N meetings in one room (Solution) |
Maximum of all subarrays of size k (Solution) |

Remove Duplicates (Solution) |
Maximum sum increasing subsequence (Solution) |
Convert array into Zig-Zag fashion (Solution) |

Subarray with given sum (Solution) |
Swap all odd and even bits (Solution) |
Count number of hops (Solution) |

Shop in Candy Store (Solution) |
Largest number possible (Solution) |
0 - 1 Knapsack Problem (Solution) |

Tom and Jerry (Solution) |
Next larger element (Solution) |
Equilibrium point (Solution) |

Recursively remove all adjacent duplicates (Solution) |
Flood fill Algorithm (Solution) |
Roman Number to Integer (Solution) |

Minimum Operations (Solution) |
Find all pairs with a given sum (Solution) |
Check if frequencies can be equal (Solution) |

Find the element that appears once in sorted array (Solution) |
Zero Sum Subarrays (Solution) |
Smallest window in a string containing all the characters of another string (Solution) |

K-th element of two sorted Arrays (Solution) |
Check whether K-th bit is set or not (Solution) |
Element with left side smaller and right side greater (Solution) |

Array Subset of another array (Solution) |
Shortest Common Supersequence (Solution) |
Rotten Oranges (Solution) |

Swapping pairs make sum equal (Solution) |
Minimum indexed character (Solution) |
Reverse a linked list (Solution) |

Rotate a Linked List (Solution) |
Pairwise swap elements of a linked list by swapping data (Solution) |
Given a linked list of 0s, 1s and 2s, sort it. (Solution) |

Add two numbers represented by linked lists (Solution) |
Detect Loop in linked list (Solution) |
Delete without head pointer (Solution) |

Diameter of Binary Tree (Solution) |
Check for Balanced Tree (Solution) |
n’th node from end of linked list (Solution) |

Left View of Binary Tree (Solution) |
Merge two sorted linked lists (Solution) |
Queue using two Stacks (Solution) |

Stack using two queues (Solution) |
Level order traversal in spiral form (Solution) |
Depth First Traversal for a Graph (Solution) |

Determine if Two Trees are Identical (Solution) |
Lowest Common Ancestor in a BST (Solution) |
Largest subarray with 0 sum (Solution) |

Print a Binary Tree in Vertical Order (Solution) |
Get minimum element from stack (Solution) |
Serialize and Deserialize a Binary Tree (Solution) |

Josephus problem (Solution) |
Check if Linked List is Palindrome (Solution) |
Maximum path sum (Solution) |

Symmetric Tree (Solution) |
Coin Change (Solution) |
Kadane’s Algorithm (Solution) |

Longest Increasing Subsequence (Solution) |
Longest Common Subsequence (Solution) |
Minimum number of jumps (Solution) |

Egg Dropping Puzzle (Solution) |
Edit Distance (Solution) |
Path in Matrix (Solution) |

Trapping Rain Water (Solution) |
Minimum Platforms (Solution) |
Longest Palindrome in a String (Solution) |

Relative Sorting (Solution) |
Special Keyboard (Solution) |
Form a palindrome (Solution) |

Coin Piles (Solution) |
Minimize the heights (Solution) |
Longest Common Substring (Solution) |

Shortest Source to Destination Path (Solution) |
Find whether path exist (Solution) |
Rearrange characters (Solution) |

First non-repeating character in a stream (Solution) |
Kth largest element in a stream (Solution) |
Geek collects the balls (Solution) |

Array Pair Sum Divisibility Problem (Solution) |
Page Faults in LRU (Solution) |
Check for BST (Solution) |

Bottom View of Binary Tree (Solution) |
Intersection Point in Y Shapped Linked Lists (Solution) |
Connect Nodes at Same Level (Solution) |

Flattening a Linked List (Solution) |
Detect cycle in a directed graph (Solution) |
Topological sort (Solution) |

Find the number of islands (Solution) |
Circular tour (Solution) |
Generate IP Addresses (Solution) |

Remove loop in Linked List (Solution) |
Implementing Dijkstra (Solution) |
Max length chain (Solution) |

Box Stacking (Solution) |
Rat in a Maze Problem (Solution) |
Maximum subset XOR (Solution) |

Largest Number formed from an Array (Solution) |
Sorting Elements of an Array by Frequency (Solution) |
Minimum Cost Path (Solution) |

N-Queen Problem (Solution) |
Solve the Sudoku (Solution) |
Find median in a stream (Solution) |