编辑代码

#include <stdio.h>
int main () {
    int number;
    int count=0;
    int sum=0;
    scanf("%d",&number);
    while(number!=-1){
        count++;
        sum+=number;
        scanf("%d",&number);
    }
    printf("%f\n",1.0*sum/count);
    return 0;
}