要求班级人数60.成绩3门 还有平均分数！

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
struct hangban
{
char hangbanhao[20];  //是字符串，不是单个字母,有原来的num没有用到，删了
char qishizhan[20];
char zhongdianzhan[20];
int yushoushu;
int yishoushu;
int feixingshijian;
};
int n=0;
struct hangban stu[100];
struct hangban *p;

void lr();
void ll();
void cx();
void xg();
void sc();

void main()
{
    int z;
    printf("+---------------------------+\n");
    printf("|  欢迎使用航空订票系统 |\n");
    printf("+---------------------------+\n");
    printf("提示：为保证您的操作得到保存，请按正常顺序退出系统^_^\n");
    do
    {
        printf("\n\t\t\t--------------------------------\n");
        printf("\t\t\t+            主菜单            |\n");
        printf("\t\t\t--------------------------------\n");
        printf("\t\t\t+    [1]----录入               |\n");
        printf("\t\t\t+    [2]----显示               |\n");
        printf("\t\t\t+    [3]----查询               |\n");
        printf("\t\t\t+    [4]----退票               |\n");
        printf("\t\t\t+    [5]----修改               |\n");
        printf("\t\t\t+    [0]----退出               |\n");
        printf("\t\t\t--------------------------------\n");
        printf("请输入您的选择：");
        scanf("%d", &z);
        switch(z)
        {
       case 0 : exit(0); break;  /* 退出系统 */
        case 1 :lr();break;
        case 2 :ll();break;
        case 3 :cx();break;
        case 4 :sc();break;
        case 5 :xg();break;
       default:printf("\n无效选项!"); break;
        }
  }
    while(z!= 0);
}

void lr()/*添加函数*/
{
int y=1;
p=stu[n];  /* 指向第一个空指针，以输入新信息 */   
do
{
   printf("--------------------\n");  
   printf("请输入飞机航班号:");　//楼主自己分清自己定义的变量是字符串还是数，输入字符串不要加上&,以下就是好多这样的错误
   scanf("%s",p->hangbanhao);  //请楼主对比红色部分修改前后的区别
   printf("请输入飞机起始站:");
   scanf("%s",p->qishizhan);
   printf("请输入飞机终点站:");
   scanf("%s",p->zhongdianzhan);
   printf("输入飞机飞行日期:");
   scanf("%d",&p->feixingshijian);
   printf("请输入预售票总数:");
   scanf("%d",&p->yushoushu);
   printf("请输入已售票总数:");
   scanf("%d",&p->yishoushu);
   n++;
   p++;
   printf("\n1.继续输入.\n0.输入完毕.\n");
   printf("请选择：");
   scanf("%d",&y);
  }
while(y==1);
printf("提示：输入完毕!你一共输入%d个\n",n);

}

void ll()/*显示函数*/
{
  int i,j;
  if(n!=0)
  { printf("航班总数:%d\n", n);
  printf("航班号\t起始站\t终点站\t飞行时间\t预售票总数\t已售票总数\t\n");
  printf("-----------------------------------------------------\n");
  for(i=0;i<n;i++)
  printf("%s\t%s\t%s\t%d\t%d\t%d\t \n",stu[i].hangbanhao,stu[i].qishizhan,stu[i].zhongdianzhan,stu[i].feixingshijian,stu
  [i].yushoushu,stu[i].yishoushu);
  }
  else printf("提示:无航班数据，请输入数据！");
}

void cx()/*查询函数*/
{
int c;
int i,j;
char name[20],w[20];  //w是字符串，以下num有一处相同
if(n!=0)
{
do{    printf("\n");
        printf("+--------------------+\n");
        printf("| 起飞城市    请按 1 |\n");
        printf("| 抵达城市    请按 2 |\n");
        printf("| 取消        请按 0 |\n");
        printf("+--------------------+\n");
        printf("请输入您的选择:");
        scanf("%d", &c);
        switch(c)
        {
            case 0:  break;
            case 1:
                   j=0;
                   printf("请输入起飞城市:");
                   scanf("%s", w);
                   printf("\n");
                   for(i=0;i<n;i++)
                   if(strcmp(stu[i].qishizhan,w)==0)  //字符串比较不能用==,只能用strcmp(),下同
                   {
                   printf("航班号\t起始站\t终点站\t飞行时间\t预售票总数\t已售票总数\t\n");
                   printf("%s\t%s\t%s\t%d\t%d\t%d\t\n",stu[i].hangbanhao,stu[i].qishizhan,stu[i].zhongdianzhan,stu            
       [i].feixingshijian,stu[i].yushoushu,stu[i].yishoushu);
                    j=1;
                   }
                   if(j==0)
                   printf("提示:没有该航班记录，请核对！");
                   break;
            case 2:
                   j=0;
                   printf("请输入抵达城市:");
                   scanf("%s", name);
                   printf("\n");
                   for(i=0;i<n;i++)
                   if(strcmp(name,stu[i].zhongdianzhan)==0)
                   {
                   printf("航班号\t起始站\t终点站\t飞行时间\t预售票总数\t已售票总数\t\n");
                   j=1;
                   printf("%s\t%s\t%s\t%d\t%d\t%d\t\n",stu[i].hangbanhao,stu[i].qishizhan,stu[i].zhongdianzhan,stu            
       [i].feixingshijian,stu[i].yushoushu,stu[i].yishoushu);
                   }
                  if(j==0)
                  printf("提示:没有该航班记录，请核对！");
                  break;
                 default:
                printf("\n提示:无效选项!");
                break;
       }

     }while(c!= 0);
   }else  printf("提示:无航班数据，请输入数据！");
}


void xg()/*修改函数*/
{
char num[20];  //字符串
int i,j,c;
if(n!=0)
{
  printf("请输入您要修改的飞机航班号：");
  scanf("%s", num);
  printf("\n");
  for(i=0;i<n;i++)
  if(strcmp(stu[i].hangbaohao)==0)
  j=i;
  do{
      printf("请选择您要修改的航班的信息内容：\n");
      printf("+----------------------+\n");
      printf("| 航班号        请按 1 |\n");
      printf("| 起始站        请按 2 |\n");
      printf("| 终点站        请按 3 |\n");
      printf("| 飞行时间      请按 4 |\n");
      printf("| 预售票总数    请按 5 |\n");
      printf("| 已售票总数    请按 6 |\n");
      printf("| 取消          请按 0 |\n");
      printf("+----------------------+\n");
      printf("请输入您的选择：");
      scanf("%d", &c);
      printf("\n");
      switch(c)
           {
        case 0:break;

        case 1:printf("请输入航班号：");
               scanf("%s",stu[j].hangbanhao);
               break;
        case 2:printf("请输入起始站：");
               scanf("%s",stu[j].qishizhan);
               break;
        case 3:printf("请输入终点站：");
               scanf("%s",stu[j].zhongdianzhan);
               break;
        case 4:printf("请输入飞行时间：");
               scanf("%d",&stu[j].feixingshijian);
               break;
        case 5:printf("请输入预售票总数：");
               scanf("%d",&stu[j].yushoushu);
               break;
        case 6:printf("请输入已售票总数：");
               scanf("%d",&stu[j].yishoushu);
               break;
        default:
                printf("\n无效选项!");
                break;
        }

    }while(c!= 0);
  }else   printf("提示:无航班数据，请输入数据！");
}


void sc()/*删除函数*/
{
char num[20];  //字符串
int i,j,e;
if(n!=0)
{
printf("航班号\t起始站\t终点站\t飞行时间\t预售票总数\t已售票总数\t\n");
  printf("-----------------------------------------------------\n");
  for(i=0;i<n;i++)
   printf("%s\t%s\t%s\t%d\t%d\t%d\t\n",stu[i].hangbanhao,stu[i].qishizhan,stu[i].zhongdianzhan,stu[i].feixingshijian,stu
[i].yushoushu,stu[i].yishoushu);
  printf("请输入您要退票的航班号：");
  scanf("%s", num);
  printf("\n");
  for(i=0;i<n;i++)
  if(strcmp(num,stu[i].hangbaohao)==0)  //你要核对的信息不要对错了自己定义的变量的意思，这样的错误好几处
    j=i;
  if(j!=(n-1))
    {
     for(;j<n-1,j++)
     {
      strcpy(stu[j].qishizhan,stu[j+1].qishizhan);
      strcpy(stu[j].zhongdianzhan,stu[j+1].zhongdianzhan);
      stu[j].feixingshijian=stu[j+1].feixingshijian;
      stu[j].yushoushu=stu[j+1].yushoushu;
      stu[j].yishoushu=stu[j+1].yishoushu;
     }
    n--;
    }else n--;  //这时里最后一张票没有清空，其实也没有必要
  printf("提示:退票成功！");
  }else    printf("提示:无任何购票记录，请购票！");
}
请参考！

是学长学姐吧，叫学哥不好听。大一的吧。都一个学期还不知道怎么叫啊？

楼上的，楼主要的是考试成绩系统，你怎么给的订票系统？

我是让她参考一下，没有说就是答案啊。

#include<stdio.h>
#include<stdlib.h>
#define N
struct
{
  int   num ;
  char  name[N];
  int   waiyu;
  int   shuxue;
  int   diannao;  
}stu[20]={{20100,"aa",88,92,86},\     /***初始化结构体数组***/
          {20101,"bb",58,69,75},\
          {20102,"cc",55,73,80},\
          {20103,"dd",58,63,57},\
          {20104,"ee",78,80,45},\
          {20105,"ff",89,69,75},\
          {20106,"gg",57,87,65},\
          {20107,"hh",88,89,95},\
          {20108,"ii",77,46,67},\
          {20109,"jj",85,75,68}};
int main()
{
    int m,n,temp,i,b[3]={0,0,0},sum[3]={0,0,0};
{
  for(i=0;i<N;i++)
  {
  sum[i]=stu[i].waiyu+stu[i].shuxue+stu[i].diannao;              /***由数组sum【】存放每个学生的总成绩***/

  b[i]=sum[i]/3.0;                                               /***由数组b【】存放每个学生的平均成绩***/
      printf("the %d'sum is %3d                     the %d'avarage is %3d\n",stu[i].num,sum[i],i,b[i]);        /***输出学生的总成绩和平均成绩***/

 }
{
   for(n=0;n<=N-2;n++)                                            /***比较学生的平均并输出***/
    for(i=0;i<N-n-1;i++)
     if(b[i]<b[i+1])
    {temp=b[i];b[i]=b[i+1];b[i+1]=temp;}
 for(i=0;i<=N-1;i++)
printf("                     the  avarage %d is the rank  %d\n",b[i],i+1);
}  

}

}

    自己编的，基本功能可以实现了。。

话说
LZ需要的是源代码还是程序？

谢谢啊！