题目链接
#include<iostream>
#include<cstdio>
#include<queue>
using namespace std;
char a[10000];
int main()
{
queue<int>A;
int i=1;a[0]=getchar();
while(a[i-1] != '@')
{
a[i]=getchar();
i++;
}
int d=i;
int u=0;
for(int i = 0 ;i < d;i++)
{
if(a[i] == '(')
{
A.push(a[i]);continue;
}
if( a[i] == ')')
{
if(A.front() == '(')
{
A.pop();
}
else{
printf("NO\n");return 0;
}
}
}
if(A.empty())
{
printf("YES\n");
}
else{
printf("NO\n");
}
return 0;
}
https://www.luogu.org/problemnew/show/P1739