NYOJ--2--括号配对问题

/*
    Name: NYOJ--2--括号配对问题
    Author: shen_渊 
    Date: 18/04/17 21:15
    Description: 先入栈个‘#’ 就好做了 
*/
#include<bits/stdc++.h> 
using namespace std;
bool cmp(char,char) ;
int main(){
    int n;cin>>n;
    while(n--){
        string str;cin>>str;
        stack<char> s;
        while(!s.empty())s.pop();
        s.push('#');//
        for(int i=0; i<str.size(); ++i){
            if(str[i]=='[' || str[i]=='(')
                    s.push(str[i]);
                else if((str[i]==']' &&s.top()=='[') || (str[i]==')' && s.top()=='('))
                    s.pop();
                else
                    s.push(str[i]);
        }
        if(s.top() != '#')cout<<"No"<<endl;
        else cout<<"Yes"<<endl;
        while(s.top() != '#')s.pop();
    }
    return 0;
}
bool cmp(char c,char cc){
    if(c == '(' && cc == ')')return 1;
    else if(c == '[' && cc == ']')return 1;
    else return 0;
}
/*
    仔细一想，于是…… 
*/
#include<bits/stdc++.h> 
using namespace std;
bool cmp(char,char) ;
int main(){
    int n;cin>>n;
    while(n--){
        string str;cin>>str;
        int a = 0,b = -1,pos; 
        while(a != b){
            a = str.size();
            while((pos = str.find("()")) != string::npos)str.erase(pos,2);
            while((pos = str.find("[]")) != string::npos)str.erase(pos,2);
            b = str.size();
        } 
        if(str == "")cout<<"Yes"<<endl;
        else cout<<"No"<<endl;
    }
    return 0;
}