코딩테스트 2번 __stack

package main4;


import java.util.Map;
import java.util.Scanner;
import java.util.Stack;
import java.util.HashMap;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;



public class Main4 {
	
	//stack.pop
	//stack.push
	//stack.peek;
	//stakc.size
	//stack.contain
	//stack.claer

	public String solution(String a ){
		
		String str  = "";
		Stack<Character> stack = new Stack<>();
	
		for(int i = 0; i < a.length(); i ++) {
			
			
				if(a.charAt(i) == ')') {
					
					while(stack.pop() != '(');
				
				} else {
					stack.push(a.charAt(i));
				}
		
		}
		
		for(int i = 0 ; i < stack.size(); i ++){
		
			str += stack.get(i);
		}
		return str ;
	};
	
	
	

	
	
	
	
	
	
	public static void main(String[] args) {
		
		
		Main4 main2 = new Main4();
		

		
		 Scanner kb = new Scanner (System.in);
		 String a=  kb.nextLine();
		
	
		
	
		
	
		System.out.println(	main2.solution(a));
	    
		
	}
	

}