请问你代码里的变量A是什么东东???
#include <stdio.h>
int main()
{
int n=0,sum=0,m;
scanf("%d",&m);
while(m!=-1)
{
sum += m;
n++;
scanf("%d",&m);
}
printf("%.1f",sum*1.0/n);
}
float score = 0;
scanf("%f", &score);
或者
ave = (float)sum/(float)n;
没给A赋初值吧