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为什么插入模块一的程序后整个程序就产生错误，一旦删除模块一的程序就能运行呢？请高手修改一下，并说说原因，谢谢！
#include "stdio.h"
#define SIZE 50
struct student
{ int n;
 int num;
 int age;
 char addr[10];
 char name[10];
 float score[3];
 float avr;
}stu[SIZE];

/*1. Input records模块一*/
void finput()
{
FILE *fp;
 int i;
 fp=fopen("fstu","wb");
 for(i=0;i<SIZE;i++)
  { printf("Input student's n=%d num,name,age,addr,maths,computer,english:",i+1);
   scanf("%d%s%d%s%f%f%f",&stu[i].num,stu[i].name,&stu[i].age,stu[i].addr,&stu[i].score[0],
  &stu[i].score[1],&stu[i].score[2] );
   stu[i].avr=(stu[i].score[0]+stu[i].score[1]+stu[i].score[2])/3.0;
   fclose(fp);
}

void fresearch()
{
}

/*3. Change the records*/
void fchange()
{
}

/*4. Append a record*/
void fappend()
{
}

/*5. List the record*/
void flist()
{ int i;
  FILE *fp;
  fp=fopen("fstu","rb");
  clrscr();
  printf("                     Student's Datas                           \n");
  printf("***************************************************************\n");
  printf("* NO. num  name   age   addr   maths   computer  english  avr *\n");
  printf("***************************************************************\n");
     for(i=0;fread(&stu[i],sizeof(struct student),1,fp)!=0;i++)
      { printf("%12d%71d %-10s%2d %-10s",stu[i].n,stu[i].num,stu[i].name,
      stu[i].age,stu[i].addr);
       printf("%3d%3d%3d%6.2f\n",stu[i].score[0],stu[i].score[1],
       stu[i].score[2],stu[i].avr);
      }fclose(fp);
      printf("*********************************************************\n\n");
      getch();
}

/*6. Sort the records*/
void fsort()
{
}

/*7. Copy the file*/
void fcopy()
{
}

/*8. Restore the file*/
void frestore()
{
}

main()
{  int n;
  clrscr();
  for(;;)
  { printf("*************************************************************\n");
    printf("*                        STUDENT M I S                      *\n");
    printf("*************************************************************\n");
    printf("*                      1. Input a record                    *\n");
    printf("*                      2. Research records                  *\n");
    printf("*                      3. Change the records                *\n");
    printf("*                      4. Append a record                   *\n");
    printf("*                      5. List the records                  *\n");
    printf("*                      6. Sort the records                  *\n");
    printf("*                      7. Copy the file                     *\n");
    printf("*                      8. Restore the file                  *\n");
    printf("*************************************************************\n");
    printf("*                      0. Exit the system                   *\n");
    printf("*************************************************************\n");
    printf("                     Please enter (0--8):                    \n");
     scanf("%d",&n);
      switch (n)
       {case 1:finput();     break;
case 2:fresearch();  break;
case 3:fchange();    break;
case 4:fappend();    break;
case 5:flist();      break;
case 6:fsort();      break;
case 7:fcopy();      break;
case 8:frestore();   break;
case 0:printf("**************************************************\n");
       printf("*                     FINISH                     *\n");
       printf("**************************************************\n");
       printf("*                    GOOD BYE                    *\n");
       printf("**************************************************\n");
   exit();
default:printf("EORROR!!!Please press any key continute!\n");
       }
  }
  getch();
}