括号匹配问题

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cstring>
#include<string>
#include<cmath>
#include<queue>
#include<vector>
#include<set>
#include<stack>
using namespace std;
int n;
char ch;
stack<char> s;
int main()
{
      scanf("%d",&n);
      getchar();
      while(n--)
      {
            while(scanf("%c",&ch)&&ch!=‘\n‘)
            {
                  if(s.empty())
                        s.push(ch);
                  else
                  {
                        if(ch==‘(‘||ch==‘[‘)
                              s.push(ch);
                        else
                        {
                              if(ch==‘)‘&&s.top()==‘(‘)
                                    s.pop();
                              else if(ch==‘]‘&&s.top()==‘[‘)
                                    s.pop();
                              else
                                    s.push(ch);
                        }
                  }
            }
            if(s.empty())
                  printf("Yes\n");
            else
                  printf("No\n");
            while(!s.empty())
                  s.pop();
      }
      return 0;
}