1. 올바른 괄호 import java.util.*; public class Main { public static void main(String[] args){ Main T = new Main(); Scanner in=new Scanner(System.in); String str = in.next(); System.out.println(T.solution(str)); return ; } public String solution(String str){ String answer = "YES"; Stack stack = new Stack(); for(char x : str.toCharArray() ){ if(x == '(') stack.push(x); else{ if(stack.isEmpty()) return..