#include <iostream>

using namespace std;

int main()
{
	float score;
	float sum = 0;
	int counter = 0;

	cin >> score;
	while(cin)
	{
		sum = sum + score;
		counter ++;
		cin >> score;
	}
	cout << "Number of students: " << counter << endl;
	cout << "Sum of scores: " << sum << endl;
	cout << "Average of scores : " << sum/counter << endl;
	return 0;
}