#include <iostream>
#include <string>
#include <cmath>
#include <cstdio>

using namespace std;

int main()
{
    int N;
    cin >> N;

    double total = 0.0;
    double tmp;

    for (int i = 0; i < N; i++)
    {
        cin >> tmp;
        total += tmp;
    }

    printf("%.10lf", total);
    cout << endl;

}