Category: algorithms

In a string S of lowercase letters, these letters form consecutive groups of the same character. For example, a string like S = “abbxxxxzyy” has the groups “a”, “bb”, …

In a town, there are N people labelled from 1 to N. There is a rumor that one of these people is secretly the town judge. If the town …

Given two strings S and T, return if they are equal when both are typed into empty text editors. # means a backspace character. Example 1: Input: S = …

In an alien language, surprisingly they also use english lowercase letters, but possibly in a different order. The order of the alphabet is some permutation of lowercase letters. Given …

Given a 2D integer matrix M representing the gray scale of an image, you need to design a smoother to make the gray scale of each cell becomes the …