package practice3_struct;

import java.util.*;

public class Question2 {

// 겹쳐진 압축 해제

public String solution(String s){

String answer = "";

Stack<String> st = new Stack<>();

for(Character x : s.toCharArray()){

if(x == ')'){

String tmp = "";

while(!st.empty()){

String c = st.pop();

if(c.equals("(")){

String num = "";

while(!st.empty() && Character.isDigit(st.peek().charAt(0))){

num = st.pop() + num;

}

String res = "";

int cnt = 0;

if(num.equals("")) cnt = 1;

else cnt = Integer.parseInt(num);

for(int i = 0; i < cnt; i++) res += tmp;

st.push(res);

break;

}

tmp = c + tmp;

}

}

else st.push(String.valueOf(x));

}

for(String x : st) answer += x;

return answer;

}

// 괄호가 있으면 무조건 스택!! , 음수 양수 짝꿍,

public static void main(String[] args){

Question2 T = new Question2();

System.out.println(T.solution("3(a2(b))ef"));

System.out.println(T.solution("2(ab)k3(bc)"));

System.out.println(T.solution("2(ab3((cd)))"));

System.out.println(T.solution("2(2(ab)3(2(ac)))"));

System.out.println(T.solution("3(ab2(sg))"));

}

}