import java.util.ArrayDeque;

import java.util.Deque;

/**

* @author JackWu

* @version 1.0

*/

public class BasicCalculator {

public static void main(String[] args) {

Solution solution = new Solution();

System.out.println(solution.calculate("(1+(4+5+2)-3)+(6+8)"));

}

static class Solution {

public int calculate(String s) {

// 计算结果

int res = 0;

// 当前数字

int num = 0;

// + - 符号

int sign = 1;

Deque<Integer> stack = new ArrayDeque<>();

for (int i = 0; i < s.length(); i++) {

char c = s.charAt(i);

if (c == ' ') {

continue;

} else if(Character.isDigit(c)) {

while (i < s.length() && Character.isDigit(s.charAt(i))) {

num = num * 10 + Integer.parseInt(String.valueOf(s.charAt(i)));

i++;

}

i--;

}else if (c == '+' || c == '-'){

sign = c == '+' ? 1 : -1;

num = 0;

}else if (c == '(') {

stack.push(res);

stack.push(sign);

res = 0;

sign = 1;

}else if (c == ')'){

sign = stack.pop();

num = res;

res = stack.pop();

}

res += sign * num;

}

return res;

}

}

}