P354.输入学生信息，创立文件，实现排序，插入

#include<stdio.h> #include<stdlib.h>

struct student {  char name[10];  int num;  float score_1;  float score_2;  float score_3;  float aver; }stu[6],temp;

void save() {FILE*fp; int i; if((fp=fopen ("stu.dat","wb"))==NULL)                {  printf("cannot open file1\n");  return; } for(i=0;i<5;i++) if(fwrite(&stu[i],sizeof(struct student),1,fp)!=1) printf("file write error\n"); fclose(fp); }

void save_1() {FILE*fp; int i; if((fp=fopen ("stu_sort.dat","wb"))==NULL)                {  printf("cannot open file4\n");  return; } for(i=0;i<5;i++) if(fwrite(&stu[i],sizeof(struct student),1,fp)!=1) printf("file write error\n"); fclose(fp); }

void save_2() {FILE*fp; int i; if((fp=fopen ("aver.dat","wb"))==NULL)                {  printf("cannot open file7\n");  return; } for(i=0;i<5;i++) if(fwrite(&stu[i],sizeof(struct student),1,fp)!=1) printf("file write error\n"); fclose(fp); }

void print() {int i; FILE*fp; if((fp=fopen("stu.dat","rb"))==NULL) {  printf("cannot open file2\n");  exit(0); } for(i=0;i<5;i++) {  fread(&stu[i],sizeof(struct student),1,fp);  printf("%s\t%d\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n",stu[i].name,stu[i].num,stu[i].score_1,stu[i].score_2,stu[i].score_3,stu[i].aver); } fclose(fp); }

void print_1() {int i; FILE*fp; if((fp=fopen("stu_sort.dat","rb"))==NULL) {  printf("cannot open file5\n");  exit(0); } printf("the aver is\n"); for(i=0;i<5;i++) {  fread(&stu[i],sizeof(struct student),1,fp);  printf("%s\t%d\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n",stu[i].name,stu[i].num,stu[i].score_1,stu[i].score_2,stu[i].score_3,stu[i].aver); } fclose(fp); }

void print_2() {int i; FILE*fp; if((fp=fopen("aver.dat","rb"))==NULL) {  printf("cannot open file8\n");  exit(0); } for(i=0;i<5;i++) {  fread(&stu[i],sizeof(struct student),1,fp);  printf("%s\t%d\t%.2lf\t%.2lf\t%.2lf\t%.2lf\n",stu[i].name,stu[i].num,stu[i].score_1,stu[i].score_2,stu[i].score_3,stu[i].aver); } fclose(fp); }

void aver() {int i,j,k,l,m; FILE*fp; if((fp=fopen("stu.dat","rb"))==NULL) {  printf("cannot open file3\n");  exit(0); } for(i=0;i<5;i++) fread(&stu[i],sizeof(struct student),1,fp); fclose(fp); for(j=0;j<4;j++) {  k=j;  for(l=j+1;l<5;l++)   if(stu[k].aver>stu[l].aver)k=l;   if(k!=j)   {    temp=stu[j];    stu[j]=stu[k];    stu[k]=temp;   } } }

void insert() { int i,j,k; FILE*fp; if((fp=fopen("stu_sort.dat","rb"))==NULL) {  printf("cannot open file6\n");  exit(0); } for(i=0;i<5;i++) fread(&stu[i],sizeof(struct student),1,fp); fclose(fp); printf("please insert data of students num,score_1,score_2,score_3,name\n"); scanf("%d,%f,%f,%f,%s",&stu[5].num,&stu[5].score_1,&stu[5].score_2,&stu[5].score_3,stu[5].name); stu[5].aver=(stu[5].score_1+stu[5].score_2+stu[5].score_3)/3; for(j=0;j<5;j++) {  if(stu[5].aver<stu[j].aver);break; } temp=stu[5]; for(k=5;k>(j+1);k--) {  stu[k]=stu[k-1]; } stu[j+1]=temp; } void main() {  int i;  printf("please enter data of students num,score_1,score_2,score_3,name\n");  for(i=0;i<5;i++)  {   scanf("%d,%f,%f,%f,%s",&stu[i].num,&stu[i].score_1,&stu[i].score_2,&stu[i].score_3,stu[i].name);   stu[i].aver=(stu[i].score_1+stu[i].score_2+stu[i].score_3)/3;  }  save();  print();  aver();  save_1();  print_1();  insert();  save_2();  print_2(); }