개발에 AtoZ까지

1. 문제 Every email consists of a local name and a domain name, separated by the @ sign. For example, in alice@leetcode.com, alice is the local name, and leetcode.com is the domain name. Besides lowercase letters, these emails may contain '.'s or '+'s. If you add periods ('.') between some characters in the local name part of an email address, mail sent there will be forwarded to the same address ..

1. 문제 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 a type of stone you have. You want to know how many of the stones you have are also jewels. The letters in J are guaranteed distinct, and all characters in J and S are letters. Letters are case sensitive, so "a" is considered a different type of stone from..