计算班级平均数
计数控制的循环
int main()
{
unsigned int counter;
int grade;
int total;
float average;
total = 0;
counter = 1;
while( counter <= 4)//需要计算的数是确定的
{
printf("enter grade: ");
scanf("%d",&grade);
total = total + grade;
counter = counter + 1;
}
average = total/4.0;//可尝试写成4
//会出现average怎么样都无法出现正确的数。因为4是整型,total也是整型
printf("class average is %f\n",average);
}
标记控制的循环
循环体结构改为
while(grade != -1)
{ total = total + grade;
counter = counter + 1;
printf("enter grade,-1 to the end")
scanf("%d",&grade);
}
if(counter != 0)
{ average = total/counter;
printf("class average is %.2f\n",average);
}
else{//if no grades were entered, output messege
{ puts("no grades were entered");}
通过标记某个条件,来结束循环
还可以强行转换数据类型
average = (float)total/counter