[2504] 괄호의 값

#include <iostream>
#include <stack>
#include <string>
using namespace std;
int checkVPS(string str);
int main()
{
	string str;
	cin >> str;
	cout << checkVPS(str) << endl;
	return 0;
}
int checkVPS(string str)
{
	stack <char> st;
	int num = 1, sum = 0;
	bool value = false;
	for (int i = 0; i < str.length(); i++)
	{
		if (str[i] == '(')
		{
			num *= 2;
			st.push(str[i]);
		}
		else if (str[i] == '[')
		{
			num *= 3;
			st.push(str[i]);
		}
		else if (str[i] == ')')
		{
			if (st.empty())
			{
				value = true;
				break;
			}
			if (str[i - 1] == '(')
			{
				sum += num;
				st.pop();
			}
			num /= 2;
		}
		else if (str[i] == ']')
		{
			if (st.empty())
			{
				value = true;
				break;
			}
			if (str[i - 1] == '[')
			{
				sum += num;
				st.pop();
			}
			num /= 3;
		}
	}
	if (value || !st.empty())
		return 0;
	else
		return sum;
}