#include <bits/stdc++.h>
using namespace std;

using ld = long double;

int main(void) {
	cout << fixed << setprecision(10);
	
	int N;
	cin >> N;
	vector<ld> A(N);
	for(int i = 0; i < N; ++i) cin >> A[i];
	
	ld ans = 0;
	for(int i = 0; i < N; ++i) ans += A[i];
	cout << ans << "\n";
	return 0;
}