12

#include<stdio.h>
struct student{
    char number[10];
    char name[20];
    int age;
    char gender[5];
    char phone[15];
    char dept[20];
    int score;
}; 
int main()
{
    
    return 0;
}

1. #include<stdio.h>
   #include<stdlib.h>
   struct student
   {
       char no[10];
       char name[20];
       int age;
   }; 
   int main()
   {
       student class3[31];
       FILE *fp=fopen("d:\input.txt","r");
       fscanf(fp,"%s%s%d",class3[0].no,class3[0].name,&class3[0].age);
       fclose(fp);
       fp=fopen("d:\output.txt","w");
       fprintf(fp,"%s    %s    %d
   ",class3[0].no,class3[0].name,class3[0].age);
       fclose(fp);    
       return 0;
   }

#include<stdio.h>
struct student{
    char sno[10];
    char sname[20];
    int age;
};
int ch;
student s1;
void addStudent()
{
    FILE *fp=fopen("c:\input.txt","a+");
    do
    {
        printf("请输入学号: ");
        scanf("%s",s1.sno);
         printf("请输入姓名: ");
         scanf("%s",s1.sname);
         printf("请输入年龄: ");
         scanf("%d",&s1.age);
         fprintf(fp,"
%s    %s    %d",s1.sno,s1.sname,s1.age);
         printf("继续添加学生信息(1:是/2:否): ");
         scanf("%d",&ch);
     }while(ch==1);
}
int main()
{
    int a; 
    printf("学生管理系统
");
    printf("1.添加学生信息
");
    printf("请输入序号:
");
    scanf("%d",&a);
    if(a==1)
        addStudent();
return 0;        
}