#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;
}
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