#include <iostream>

using namespace std;


int main(){
	int n, len, num;

	cin >> n;

	for(int i = 0; i < n; i++){
		cin >> len;
		int arr[len];
		for(int j = 0; j < len; j++){
			cin >> num;
			arr[j] = num;
		}

		int index = (len/2);

		cout << "Case " << i+1 << ": " << arr[index] << endl; 

	}
	return 0; 
}