程序代码：

此程序功能是：输入两个学生的学号、姓名、成绩，输出成绩高的学号、姓名、成绩。

错误信息为：

error C2224: left of '.st1' must have struct/union type
error C2224: left of '.st2' must have struct/union type


# include <stdio.h>
int main (void)
{
    struct Student
    {
        int num;
        char name[21];
        int score;
    };
    struct Student st1,st2;
    scanf ("%d %s%d",&st1.num,st1.name,&st1.score);
    scanf ("%d %s%d",&st2.num,st2.name,&st2.score);
    if (st1.score>st2.score)
    {
        printf("num is %d\n name is %s\n score is %d",
        st1.num,st1.name.st1.score);

    }
    else if (st1.score<st2.score)
    {
        printf("num is %d\nname is %s\nscore is %d",
        st2.num,st2.name.st2.score);
    }
    else
    {
        printf("num is %d\nname is %s\nscore is %d",
        st1.num,st1.name.st1.score);
        printf("\n");
        printf("num is %d\nname is %s\nscore is %d",
        st2.num,st2.name.st2.score);
    }
    getch();
}