Given an array target and an integer n. In each iteration, you will read a number from list = {1,2,3..., n}. Build the target array using the following operations: You…

A valid parentheses string is either empty (""), "(" + A + ")", or A + B, where A and B are valid parentheses strings, and + represents string concatenation.…

Given an array of integers nums. A pair (i,j) is called good if nums == nums and i < j. Return the number of good pairs. Example 1: Input: nums…

Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string. Return a list of all possible strings we could create. Examples:…

Given an array of strings products and a string searchWord. We want to design a system that suggests at most three product names from products after each character of searchWord…

Given two strings: s1 and s2 with the same size, check if some permutation of string s1 can break some permutation of string s2 or vice-versa (in other words s2…

Given a string s, the power of the string is the maximum length of a non-empty substring that contains only one unique character. Return the power of the string. Example…

Given a list of dominoes, dominoes = is equivalent to dominoes = if and only if either (a==c and b==d), or (a==d and b==c) – that is, one domino can…