Given a gif, each cell can have one of the three values. 0 for empty, 1 for fresh Orange and 2 for rotten. Return minimum number of minutes that must elapse until no cell has a fresh Orange
Traverse a tree or a graph using DFS and BFS
Given a an array of Sorted K linked lists, merge all K lists in one Sorted linked-list and return it.
Find two numbers that add up to a Target. Find two numbers in a sorted array that add up to a number. Find three numbers in an array that add up to a Target.