#include <stdio.h>

int main(void)
{
    double a[500000], sum = 0;
    int n;
    scanf("%d", &n);
    for (int i = 0; i < n; i++) scanf("%lf", &a[i]);
    for (int i = 0; i < n; i++) sum += a[i];
    printf("%f\n", sum);
    return 0;
}