Data Structures & Algorithms

Arrays, Tree, Linked List, Heap, Dynamic Programming, Recursion, Backtracking etc.
Search term should be '3' to '100' character long.
Longest substring without repeating characters

Check if two strings are equal or not after processing backspace

Two Sum - return index of a pair of array elements with a given sum

Print all Subsets (Power Set) of a given array

Construct a Binary Tree from given Inorder and Preorder traversals

Longest Common Prefix in an Array of Strings

Word Break Problem (Using HashMap and DP)

Find a triplet in an array that sums to a given number

Rain water trapping problem - O(n) time & O(n) space

Count the number of inversions in an array - in O(n log n) time