C语言实现学生证管理程序

#include<stdio.h>
#include<malloc.h>
#include<string.h>
#include<stdlib.h>
#define STU struct student
 STU
  {long num;
   char name[20];
   int sex;
   long classes;
   long birth;
  };

/***************************input****************************/
void input(int k,STU *st)
 {int n,i;
  FILE *fp; 
  long b;
  STU student_1;
  printf("Please input your number[       ]\b\b\b\b\b\b\b");
  scanf("%ld",&b);
  for(i=0;i<k;i++)
   if(st[i].num==b) 
     {printf("\nThe school number is repeat!\n");
      free(st);menu();}
   else
     {printf("\nPlease input your name[        ]\b\b\b\b\b\b\b\b\b");
      scanf("%s",student_1.name);
      printf("\nPlease input you sex male(1) or female(2)[       ]\b\b\b\b\b\b\b");
      scanf("%d",&student_1.sex);

      printf("\nPlease input you Class[       ]\b\b\b\b\b\b\b");
      scanf("%ld",&student_1.classes);
       printf("\nPlease input you date of birth[       ]\b\b\b\b\b\b\b");
       scanf("%ld",&student_1.birth);
       fp=fopen("student1.txt","ab");
 if(!fp)
    {printf("Document error! ");
     exit(0);}
  else
{fprintf(fp,"%ld%s%d%ld%ld",b,student_1.name,student_1.sex,student_1.classes,student_1.birth);
printf("%ld%s%d%ld%ld",b,student_1.name,student_1.sex,student_1.classes,student_1.birth);
         n=k+1;
         rewind(fp);
         fprintf(fp,"%d",n);
         fclose(fp);
         free(st);
         menu();}
}}
/******************************inquiries********************************/
 void inquiries(int k,STU *st)
  {int i,j=0,n,p,w;
   long a;
   do
    {printf("\n\t\t**************INQUIRIE MENU**************\n\n");
     printf("\t\t\t1.Inquiries school number\n");
     printf("\t\t\t2.Inquiries classes\n");
     printf("\t\t\t3.Inquiries date of birth\n");
     printf("\t\t\t4.Back to menu\n");
     printf("\n\n\t\t******************************************\n");
     printf("Choice your number(1-4)[       ]\b\b\b\b\b\b\b");