#include <stdio.h>
#include <stdlib.h>

int main()
{
    printf("Input numbers.  I'll sum them up when you input a non-number.\n");
    int num_read;
    double value_read;
    double sum=0;
    while (1) {
        num_read = scanf("%lf", &value_read);
        if (num_read == 0) {
            break;
        }
        sum = sum + value_read;
    }
    printf("Sum: %f\n",sum);
    return EXIT_SUCCESS;
}