#include <iostream>
#include <numeric>
#include <vector>

using namespace std;

int main() {
	vector<double> vd{5.0,9.9,2.0,3.6,7.1,8.0,4.5};
	double avg = std::accumulate(vd.begin(), vd.end(), 0.0)/vd.size();
	cout << avg << endl;
}