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有如下结构体 struct Student{ char name[16]; int age; double math_score; double chinese_score; double english_score; double physics_score; double chemistry_score; double bio_score; }; 申请该结构体数组，容量为5，初始化5个学生的信息 使用fprintf将数组中的5个学生信息，保存到文件中去 下一次程序运行的时候，使用fscanf，将文件中的5个学生信息，写入(加载)到数组中去，并直接输出学生信息

  1 #include <stdio.h>2 #include <string.h>3 #include <stdlib.h>4 #include <sys/types.h>5 #include <unistd.h>6 #include <sys/stat.h>7 #include <fcntl.h>8 #include <pthread.h>9 #include <semaphore.h>10 #include <wait.h>11 #include <signal.h>12 #include <sys/socket.h>13 #include <arpa/inet.h>14 #include <sys/socket.h>15 #include <sys/ipc.h>16 #include <sys/sem.h>17 #include <semaphore.h>18 #include <sys/msg.h>19 #include <sys/shm.h>20 #include <sys/un.h>21 typedef struct student22 {23     char name[16];24     int age;25     double math_score;26     double chinese_score;27     double english_score;28     double physics_score;29     double chemistry_score;30     double bio_score;31 }information;32 int main(int argc, const char *argv[])33 {34     //向堆区空间申请容量为5的内存空间35     information *students=(information*)malloc(5*sizeof(information));36     if(!students)37     {38         perror("students:");39         return -1;40     }41     //循环写入学生信息42     for(int i=0;i<5;i++)43     {44         printf("输入学生姓名：");45         scanf(" %15s",students[i].name);46         printf("输入学生年龄：");47         scanf(" %d",&students[i].age);48         printf("输入学生数学成绩：");49         scanf(" %lf",&students[i].math_score);50         printf("输入学生语文成绩：");51         scanf(" %lf",&students[i].chinese_score);52         printf("输入学生英语成绩：");53         scanf(" %lf",&students[i].english_score);54         printf("输入学生化学成绩：");55         scanf(" %lf",&students[i].chemistry_score);56         printf("输入学生生物成绩：");                                                                                                                                                                                                                                                                                                                                                                                  57         scanf(" %lf",&students[i].bio_score);58     }59     //打开文件60     FILE *wfp=fopen(argv[1],"w");61     if(!wfp)62     {63         perror("wfp:");64         return -1;65     }66     //将信息录入文件中67     for(int i=0;i<5;i++)68     {69         fprintf(wfp,"姓名:%s\n年龄:%d\n数学成绩:%.1f\n语文成绩:%.1f\n英语成绩:%.1f\n化学成绩:%.1f\n生物成绩:%.1f\n",\70             students[i].name,students[i].age,students[i].math_score,students[i].chinese_score,students[i].english_score,\71             students[i].chemistry_score,students[i].bio_score);72     }73     //关闭文件74     fclose(wfp);75     //打开文件76     FILE *rfp=fopen(argv[2],"r");77     if(!rfp)78     {79         perror("rfp:");80         return -1;81     }82     //循环将文件内容赋值给结构体数组83     for(int i=0;i<5;i++)84     {85         if(fscanf(rfp,"姓名:%15s\n年龄:%d\n数学成绩:%lf\n语文成绩:%lf\n英语成绩:%lf\n化学成绩:%lf\n生物成绩:%lf\n",students[i].name,&students[i].age,&students[i].math_score,\86                 &students[i].chinese_score,&students[i].english_score,&students[i].chemistry_score,&students[i].bio_score)!=7)87         {88             perror("rfp:");89             free(students);90             return -1;91         }92     }93     //循环输出数组元素94     for(int i=0;i<5;i++)95     {96         printf("姓名:%s\n年龄:%d\n数学成绩:%.1f\n语文成绩:%.1f\n英语成绩:%.1f\n化学成绩:%.1f\n生物成绩:%.1f\n",\97             students[i].name,students[i].age,students[i].math_score,students[i].chinese_score,students[i].english_score,\98              students[i].chemistry_score,students[i].bio_score);99     }
100     //关闭文件
101     fclose(rfp);
102     //释放内存
103     free(students);
104     students=NULL;
105     return 0;
106 }
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