到底怎么改啊？？？？

#include "stdio.h"
struct stu /*结构体类型在主函数外部定义后，其即为全局结构体类型*/
{char name[20];
char sex;
long num;
float score[3];
};
main()
{struct stu student;
int i;
float sum = 0.0;
clrscr();
printf("Input student NAME:" );
gets(student.name);
printf("Input student SEX:");
student.sex = getchar();
printf("Input student NUM:");
scanf( "%ld",&student.num);
for(i = 0; i<3;i++)
{printf("\n Input student score[%d]:",i);
scanf( "%f",&student.score[i]);
sum += student.score[i];
}
printf("%s %c average=%f\n",student.name,student.sex,sum / 3);
}

clrscr();
这个看上去是turbo c特有的。
你用的是turbo c编译的么？
或者#include <stdlib>后换成
system("cls");