#include<stdio.h>
#define HEG 0.54
void height(float father,float mother)
{
    float son;
    son=(father+mother)*HEG;
    printf("son height is\n");
    printf("%0.2f",son);
}
int main()
{
    float father;
    float mother;
    printf("please input father height\n");
    scanf("%f",&father);
    printf("please input mother height\n");
    scanf("%f",&mother);
    height(father,mother);
}

你好：

  你这句代码写错了，应该改成son=height(father,mother);

明白，谢谢指点