LeetCode 20: Valid Parentheses, Why Equal Counts Are Not Enough
Problem Requirement You are given a string s containing only these six characters: ( ) { } [ ] Determine whether the string is valid. A valid string must satisfy all three conditions: Every opening bracket is closed by the same type of closing bracket. Opening brackets are closed in the correct order. Every closing bracket has a corresponding opening bracket of the same type. Return True when all conditions hold; otherwise, return False. ...