9 docs tagged with "backtracking"

This question is asked by Apple. Given a list of positive numbers without duplicates and a target number, find all unique combinations of the numbers that sum to the target.

This question is asked by Facebook. Given an integer N, where N represents the number of pairs of parentheses (i.e. "(" and ")") you are given, return a list containing all possible well-formed parentheses you can create.

This question is asked by Amazon. Given a string s consisting of only letters and digits, where we are allowed to transform any letter to uppercase or lowercase, return a list containing all possible permutations of the string.

This question is asked by Google. Given a string of digits, return all possible text messages those digits could send.

Given an array of words, return the length of the longest phrase, containing only unique characters, that you can form by combining the given words together.

This question is asked by Google. Given a string s, return all possible partitions of s such that each substring is a palindrome.

This question is asked by Amazon. Given a 2D matrix that represents a gold mine, where each cell's value represents an amount of gold, return the maximum amount of gold you can collect given the following rules:

Given a string s, remove the minimum number of parentheses to make s valid. Return all possible results.

This question is asked by Amazon. Given a 2D board that represents a word search puzzle and a string word, return whether or the given word can be formed in the puzzle by only connecting cells horizontally and vertically.