括号配对

题目传送门：点击打开链接

早上爬起来就只写了这一个题，苦逼。两种方法。

//使用stl求解 
#include <iostream>
#include <cstring>
#include <string>
#include <algorithm>
using namespace std;

string s ;
int pos = 0;

void del(string s, int & pos) {
	int flag = 1;
	for (int i =0; i<s.size() && flag; i++) {
		if ((s[i] == '(' && s[i+1] == ')') || (s[i] == '[' && s[i+1] == ']'))
		{
			pos = i;
			flag = 0;
		}
	}
	if (flag == 1)
		pos = -5;
}


int main() {
	int n;
	cin >> n;
	while (n --) {
		cin >> s;
		del(s, pos);
		while (pos>=0 && s.size()>0) {
			s.erase(pos, 2);
			del(s, pos);
		}
		
		if (pos < 0 && s.size() == 0)
			cout << "Yes"<< endl;
		else
			cout << "No"<< endl;
	}
	return 0;
}

//使用栈 
#include <iostream>
#include <string>
#include <stack>
using namespace std;

int main() {
	int n;
	cin >> n;
	while (n --) {
		int flag = 0;
		string s ;
		cin >> s;
		stack <char> p;
		for (int i = 0; i<s.size() && flag == 0; i++) {
			if (s[i] == '(' || s[i] == '[')
				p.push(s[i]);
			else {
				if (p.empty())
					flag = 1;
				else if ((s[i] == ')' && p.top() == '(') || (s[i] == ']' && p.top() == '['))
					p.pop();
				else
					p.push(s[i]);
			}
		}
		
		if (!p.empty() || flag == 1)
			cout << "No"<< endl;
		else
			cout << "Yes"<< endl;
	}
	return 0 ;
}