>>766
#include <stdio.h>
int main(void){
int i, n, sum, a[100];
i = 0;
do {
scanf("%d", &a[i]);
} while(a[i++] >= 0 && i < 100);
n = i;
sum = a[0];
for(i = 1; i < n; i++) sum += a[i];
printf("和: %d, 平均: %lg\n", sum, (double)sum / (double)n);
return 0;
}