#include<stdio.h>
int main()
{int i,b,c,n,k,sum=0;
scanf("%d",&c);
for(i=1;i<=c;i++)
scanf("%d",&n);

for(b=0;b<n;b++)
{scanf("%d",&k);
sum=sum+k;}
printf("case%d:%d\n",i,sum/n);
sum=0;
}
return 0;

}