ProblemE

题目：https://www.nowcoder.com/practice/3bad4a646b5b47b9b85e3dcb9488a8c3?tpId=40&tqId=30993&tPage=2&rp=2&ru=/ta/kaoyan&qru=/ta/kaoyan/question-ranking

栈的简单应用，但也写了二十多分钟

代码

#include <cstdio>
#include <stack>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;
string table = "(){}[]";
stack<char> s;
int main(){
    int n;
    while(scanf("%d", &n) != EOF){
        getchar();
        for(int i = 0; i < n; i++){
            string input;
            getline(cin, input);
            while(!s.empty()) s.pop();  // 清空栈
            s.push('#');
            for(int j = 0; j < input.size(); j++){
                if(table.find(input[j]) != string::npos){
                    int pos = table.find(input[j]);
                    if(pos % 2 == 0){
                        s.push(input[j]);
                        continue;
                    }
                    if(s.top() == table[pos - 1]){
                        s.pop();
                    } else s.push(input[j]);
                }
            }
            if(s.size() == 1) printf("yes\n");
            else printf("no\n");
        }
    }
}