Untitled

#include <iostream>
#include <string>
using namespace std;

int main()
{
	int n1, n2, n3, n4, n5;
	cin >> n1 >> n2 >> n3 >> n4 >> n5;
	double b = (n1 + n2 + n3 + n4 + n5)/(double)5;
	cout << b;
	return 0;
}