[C++]백준 9012: 괄호

www.acmicpc.net/problem/9012

9012번: 괄호

#include <iostream>
#include <stack>

using namespace std;

int main() {
	int n;
	cin >> n;
	while (n--)
	{
		stack<char> st;
		string c, r;
		cin >> c;

		for (int i = 0; i < c.length(); i++) {
			if (c[i] == '(') st.push(c[i]);
			else if (st.empty() && c[i] == ')') r = "NO";
			else if (c[i] == ')') st.pop();
		}
		if (st.empty() && r == "")r = "YES";
		else r = "NO";

		cout << r << endl;
	}
}