#include <bits/stdc++.h>
#define For(i, a, b) for(long long i = a; i < b; i++)
#define rep(i, n) For(i, 0, n)
#define rFor(i, a, b) for(long long i = a; i >= b; i--)
#define ALL(v) (v).begin(), (v).end()
#define rALL(v) (v).rbegin(), (v).rend()
using namespace std;

using lint = long long;
using ld = long double;

int main() {
    int n;
    cin >> n;
    ld ans = 0;
    rep(i, n) {
        ld a;
        cin >> a;
        ans += a;
    }
    cout << fixed << setprecision(10) << ans << endl;
}