#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int maxn = 1e6+7;
int main()
{
 	long double a,sum = 0.0;
 	while (scanf("%Lf",&a) != EOF)
	 	sum += a;
	printf("%.5Lf",sum);
 	return 0;
}