#include<stdio.h>
#define ST 5
struct student
{  char name[10];
   char num[10];
   int score[3];
   float ave;
   }stud[ST];
void main()
{
  void save(void);
  int i;
  float sum[ST];
  FILE *fp1;
  for(i=0;i<ST;i++)
  {
      scanf("%s %s %d %d %d",&stud[i].name,&stud[i].num,&stud[i].score[0],&stud[i].score[1],&stud.score[2]);
   sum[i]=stud[i].score[0]+stud[i].score[1]+stud[i].score[2];
   stud[i].ave=sum[i]/3;
  }
   save();
   /*用只读方式打开stu.dat*/
   fp1=fopen("stu.dat","rb");
   printf("\n name   NO.   score1   score2   score3   ave\n");
   printf("..............................................\n");
   for(i=0;i<ST;i++)
      {
       fread(&stud[i],sizeof(struct student),1,fp1);
       printf("%-10s%3d%7d%7d%7d%8.2f\n",stud[i].name,stud[i].num,stud[i].score[0],stud[i].score[1],stud[i].score[2],stud[i].ave);

   }
   flcose(fp1);
}
   

void save(void)
{
  FILE *fp;
  int i;
  if((fp=fopen("stu.dat","wb"))==NULL)
  {prutf("the file xan mot open\n");
  return;}
  for(i=0;i<ST;i++)
      if(fwrite(&stud[i],sizeof(struct student),1,fp)!=1)
      {printf(the fie can open\n);
      return;}
      fclose(fp);
}

#include<stdio.h>
#define ST 5

struct student
{  char name[10];
   char num[10];
   int score[3];
   float ave;
   }stud[ST];

void main()
{
  void save(void);
  int i;
  float sum[ST];
  FILE *fp1;
  for(i=0;i<ST;i++)
  {
      scanf("%s%s%d%d%d",stud[i].name,stud[i].num,stud[i].score[0],stud[i].score[1],stud->score[2]);
        sum[i]=stud[i].score[0]+stud[i].score[1]+stud[i].score[2];
        stud[i].ave=sum[i]/3;
  }
   save();
   /*用只读方式打开stu.dat*/
   fp1=fopen("stu.dat","rb");
   printf("\n name   NO.   score1   score2   score3   ave\n");
   printf("..............................................\n");
   for(i=0;i<ST;i++)
      {
       fread(&stud[i],sizeof(struct student),1,fp1);
       printf("%-10s%3d%7d%7d%7d%8.2f\n",stud[i].name,stud[i].num,stud[i].score[0],stud[i].score[1],stud[i].score[2],stud[i].ave);

   }
   fclose(fp1);
}
   

void save(void)
{
  FILE *fp;
  int i;
  if((fp=fopen("stu.dat","wb"))==NULL)
  {printf("the file xan mot open\n");
  return;}
  for(i=0;i<ST;i++)
      if(fwrite(&stud[i],sizeof(struct student),1,fp)!=1)
      {
          printf("the fie can open\n");
            return;
      }
      fclose(fp);
}

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