1 test case failed

#include
using namespace std;
int main() {
int tc;
cin>>tc;
for(int i=0;i<tc;i++){
int n;
cin>>n;
int a[n],b[n+1];
b[0]=0;
for(int j=0;j<n;j++){
cin>>a[j];
b[j+1]=b[j]+a[j];
b[j+1]=b[j+1]%n;
}
int count=0;
for(int j=0;j<=n;j++){
for(int k=j+1;k<=n;k++){
if(b[j]==b[k])
count++;
}
}
cout<<count<<endl;
}
return 0;
}