#include <iostream>

using namespace std;

int main()
{
        int num;
	int sum = 0;
	int counter = 0;
	float avg;

        cin >> num;             // priming read
        while(num != -1)
        {
		counter ++;
                sum = sum + num;    // process
                cin >> num;     // read next
        }
	
	avg = float(sum)/counter;
	cout << "Average: " << avg  << endl;

        return 0;
}