HDU 5650 so easy

n不为1的时候输出a[1]，否则输出0

#include<cstdio>
#include<cstring>
#include<cmath>
#include<queue>
#include<algorithm>
using namespace std;long long y[];int main()
{
    int n;
    int T;
    scanf("%d",&T);    while(T--)
    {
        scanf("%d",&n);
        long long ans;
        for(int i=;i<=n;i++) scanf("%lld",&y[i]);
        if(n==) ans=y[];
        else ans=;
        printf("%lld\n",ans);
    }
    return ;
}