int main (){ int num,sum,i;int a[100];double each;sum=0;scanf("%d",&num);each=num;for(i=0;i<num;i++){ scanf("%d",&a[i]);sum+=a[i];} printf("%d\n",sum);each/=sum;printf("%.2f",each);return 0;} each 没有被num赋值 数组下标是从0开始到最大-1 实际...