Freaks City

Valid Parentheses The solution utilizes a stack data structure to validate parentheses. When encountering an opening bracket, it is pushed onto the stack. For closing brackets, the algorithm checks whether the top of the stack matches the corresponding opening bracket. If not, the input is invalid. After processing all characters, a valid expre ...

Given a string s containing only the characters '(', ')', '{', '}', '[', and ']', determine if the string is valid. A valid string satisfies: Every opening bracket must be closed by a matcihng bracket of the same type. Brackets must close in the correct order. Each closing bracket croresponds to an opening bracket of the same type. Example 1: ...