括号配对

//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 ;
}