Description https://leetcode.com/problems/remove-vowels-from-a-string/ Given a string s, remove the vowels ‘a’, ‘e’, ‘i’, ‘o’, and ‘u’ from it, and return the new string. Example 1: Input: s =…

Description https://leetcode.com/problems/reverse-words-in-a-string/ Given an input string s, reverse the order of the words. A word is defined as a sequence of non-space characters. The words in s will…

Description https://leetcode.com/problems/to-lower-case/ Implement function ToLowerCase() that has a string parameter str, and returns the same string in lowercase. Example 1:…

Description https://leetcode.com/problems/find-and-replace-in-string/ To some string S, we will perform some replacement operations that replace groups of letters with new ones (not necessarily the…

Description https://leetcode.com/problems/jewels-and-stones/ You’re given strings J representing the types of stones that are jewels, and S representing the stones you have.  Each character in S is…

Description https://leetcode.com/problems/cracking-the-safe/ There is a box protected by a password. The password is a sequence of n digits where each digit can be…

Description https://leetcode.com/problems/expressive-words/ Sometimes people repeat letters to represent extra feeling, such as “hello” -> “heeellooo”, “hi” -> “hiiii”.  In these…

Description https://leetcode.com/problems/isomorphic-strings/ Given two strings s and t, determine if they are isomorphic. Two strings s and t are isomorphic if the characters in s can be replaced to get t.…

Description https://leetcode.com/problems/most-common-word/ You are playing the Bulls and Cows game with your friend. You write down a secret number and ask your…

Description https://leetcode.com/problems/most-common-word/ Given a paragraph and a list of banned words, return the most frequent word that is not in the…