有二十个学生 每个学生有6门课成绩（数学 语文 英语 化学 物理 生物） 从键盘上输入以上数据（包括学号 姓名 6门课成绩） 计算出每个人的总成绩 各科平均成绩 并按成绩排名。
#include<stdio.h>
struct student
{
    int num;
    char name[10];
    float math,yuwen,english,huaxue,physic,shengw;
    float sum1,average;
}stu[20];
void main()
{
    void sort(float*p);
    struct student*p1=stu;
    int i;
    float sum,aver;
    for(i=0;i<20;i++)
    {
        printf("学号：");
        scanf("%d",&p1->num);
        printf("姓名：");
        scanf("%s",p1->name);
        printf("各门成绩：");
        scanf("%f %f %f %f %f %f",&p1->math,&p1->yuwen,&p1->english,&p1->huaxue,&p1->physic,&p1->shengw);
    }
    for(p1=stu;p1<stu+20;p1++)
    {
        sum=p1->math+p1->yuwen+p1->english+p1->huaxue+p1->physic+p1->shengw;
        printf("总分：%f",sum);
        aver=sum/6;
        printf("平均分：%f",aver);
        sum=0;
    }
    for(i=0;i<20;i++)
    sort(p1->sum1);
    for(i=0;i<20;i++)
        printf("%d %s %f %f %f %f %f %f",p1->num,p1->name,p1->math,p1->yuwen,p1->english,p1->huaxue,p1->physic,p1->shengw);
}
void sort(struct student*p)
{
    int i,j;
    float swap;
    for(i=0;i<19;i++)
        for(j=i+1;j<20;j++)
            if(p[i]<p[j])
            {
                swap=p[i];
                p[i]=p[j];
                p[j]=swap;
            }
}
大神帮我改一下，谢谢啦，分不多，见谅，先谢过！

和我们的课程设计差不多啊？

#include<stdio.h>

 struct student

 {
     int num;
     char name[10];
     float math,yuwen,english,huaxue,physic,shengw;
     float sum1,average;

 }stu[20];



 void main()

 {
     struct student p;
     int i,j;

 
     for(i=0;i<20;i++)
     {
         printf("学号：");
         scanf("%d",&stu[i].num);
         printf("姓名：");
         scanf("%s",&stu[i].name);
         printf("各门成绩：");
         scanf("%f %f %f %f %f %f",&stu[i].math,&stu[i].yuwen,&stu[i].english,&stu[i].huaxue,&stu[i].physic,&stu[i].shengw);
     }
     for(i=0;i<20;i++)
     {
         stu[i].sum1=stu[i].math+stu[i].yuwen+stu[i].english+stu[i].huaxue+stu[i].physic+stu[i].shengw;
         stu[i].average=stu[i].sum1/6;
         printf("学号：%d",stu[i].num);
         printf("姓名：%s",stu[i].name);
         printf("总分：%f",stu[i].sum1);
         printf("平均分：%f",stu[i].average);
     }
     for(i=0;i<20;i++)
     {
         for(j=i+1;j<20;j++)
             if(stu[i].sum1<stu[j].sum1)
             {
                 stu[i]=p;
                 p=stu[j];
                 stu[j]=p;
             }
     }
     for(i=0;i<20;i++)
         printf("%d %s %f %f %f %f %f %f",stu[i].num,stu[i].name,stu[i].math,stu[i].yuwen,stu[i].english,stu[i].huaxue,stu[i].physic,stu[i].shengw);

 }


 

改过，但是要你自己测试吧！ 输入20组数据。。。

#include<stdio.h>
struct student
{
    int num;
    char name[10];
    float math,yuwen,english,huaxue,physic,shengw;
    float sum1,average;
}stu[20];
void main()
{
    void sort(struct student*p);
    struct student*p1=stu;
    int i;
    float sum,aver;
    /*
    1
    sdfsdf
    1 2 3 4 5 6
    2
    sdfsgg
    2 3 4 5 6 7
    3
    sdflkj
    4 5 6 7 8 9
    */
    for(p1=stu;p1<stu+3;p1++)
    {
        printf("学号：");
        scanf("%d",&p1->num);
        getchar();
        printf("姓名：");
        scanf("%s",p1->name);
        printf("各门成绩：");
        scanf("%f %f %f %f %f %f",&p1->math,&p1->yuwen,&p1->english,&p1->huaxue,&p1->physic,&p1->shengw);
    }
    for(p1=stu;p1<stu+3;p1++)
    {
        p1->sum1=p1->math+p1->yuwen+p1->english+p1->huaxue+p1->physic+p1->shengw;
        printf("总分：%f",p1->sum1);
        p1->average=p1->sum1/6;
        printf("平均分：%f",p1->average);
        printf("\n");
    }
    printf("\n");
    sort(stu);
    for(p1=stu;p1<stu+3;p1++)
        printf("%-5d %s %-5.1f %-5.1f %-5.1f %-5.1f %-5.1f %-5.1f\n",p1->num,p1->name,p1->math,p1->yuwen,p1->english,p1->huaxue,p1->physic,p1->shengw);
}
void sort(struct student*p)
{
    int i,j;
    student swap;
    for(i=0;i<19;i++)
        for(j=i+1;j<20;j++)
            if(p[i].sum1<p[j].sum1)
            {
                swap=p[i];
                p[i]=p[j];
                p[j]=swap;
            }
}

#include <stdio.h>
#include <malloc.h>

typedef struct {
    int stu_no;
    char name[10];
    float math, chinese, english, chemistry, physics, biology, total, average;
} struct_stu;

int main() {
    struct_stu * student[20], * tmp;
    int i, j;
    for (i = 0; i < 20; i++) {
        student[i] = (struct_stu *) malloc(sizeof(struct_stu));
        printf("\n学号：");
        fflush(stdout);
        scanf("%d", &student[i]->stu_no);
        printf("姓名：");
        fflush(stdout);
        scanf("%s", &student[i]->name);
        printf("各门成绩：");
        fflush(stdout);
        scanf("%f %f %f %f %f %f",&student[i]->math, &student[i]->chinese, &student[i]->english,
              &student[i]->chemistry, &student[i]->physics, &student[i]->biology);
        student[i]->total = student[i]->math + student[i]->chinese + student[i]->english +
                            student[i]->chemistry + student[i]->physics + student[i]->biology;
        student[i]->average = student[i]->total / 6;
    }
    for (i = 0; i < 19; i++) {
        for (j = i + 1; j < 20; j++) {
            if (student[j]->total > student[i]->total) {
                tmp = student[i];
                student[i] = student[j];
                student[j] = tmp;
            }
        }
    }
    for (i = 0; i < 20; i++) {
        printf("\n%2d    ", i + 1);
        printf("学号：%-6d", student[i]->stu_no);
        printf("姓名：%-10s", student[i]->name);
        printf("各门成绩：%6.2f %6.2f %6.2f %6.2f %6.2f %6.2f",
                student[i]->math, student[i]->chinese, student[i]->english,
                student[i]->chemistry, student[i]->physics, student[i]->biology);
    }
    return 0;
}
    

[ 本帖最后由 voidx 于 2011-6-7 16:48 编辑 ]

sort(p1->sum1);括号里面也应该是结构体类型吧
sum初始化下，因为没有初始化的值是不确定度 以防万一

sort(p1->sum1);
你前面不是定义了 里面是指针啊这里是指传递 不会改变实参
差不多就这些 自己在仔细看看吧