#include <stdio.h>

int main(void)
{
    int n, tmp, sum;
    while((scanf("%d", &n) == 1) && n != 0)
    {
        sum = 0;
        while(n--)
        {
            scanf("%d", &tmp);
            sum += tmp;
        }
        printf("%d\n", sum);
    }
    return 0;
}