student_management_system.txt

学生成绩管理系统,用C编的,比较简单,但很经典

学生成绩管理系统

 
/*头文件*/
#include <stdio.h>
#include<dos.h>
#include<stdlib.h>   /*其它说明*/
#include<string.h>   /*字符串函数*/
#include<mem.h>      /*内存操作函数*/
#include<ctype.h>    /*字符操作函数*/
#include<alloc.h>    /*动态地址分配函数*/
#define LEN sizeof(STUDENT)
typedef struct stu   /*定义结构体数组用于缓存数据*/
{char num[6];
 char name[5];
 int score[3];
 int sum;
 float average;
 int order;
 struct stu *next;
}STUDENT;

/*函数原型*/
STUDENT  *init();    /*初始化函数*/
int menu_select();   /*菜单函数*/
STUDENT *create();   /*创建链表*/
void print(STUDENT *head);   /* 显示全部记录*/
void search(STUDENT *head);    /*查找记录*/
STUDENT *delete(STUDENT *head);   /*删除记录*/
STUDENT *sort(STUDENT *head);    /*排序*/
STUDENT *insert(STUDENT *head,STUDENT *new);   /*插入记录*/
void save(STUDENT *head);     /*保存文件*/
STUDENT *load();        /*读文件*/

/*主函数界面*/
main()
{STUDENT *head,new;
 head=init();       /*链表初始化,使head的值为NULL*/
 for(;;)            /*循环无限次*/
   {switch(menu_select())    
      {                     
     case 1:head=create();break;
     case 2:print(head);break;
     case 3:search(head);break;
     case 4:head=delete(head);break;
     case 5:head=sort(head);break;
     case 6:head=insert(head,&new);break;  /*&new表示返回地址*/
     case 7:save(head);break;
     case 8:head=load(); break;
     case 9:exit(0);       /*如菜单返回值为9则程序结束*/
      }
   }
}

/*初始化函数*/
STUDENT *init()
{
 return NULL;  /*返回空指针*/
}

/*菜单选择函数*/
menu_select()
{int n;
 struct date d;     /*定义时间结构体*/
 getdate(&d);      /*读取系统日期并把它放到结构体d中*/
 printf("press any key to enter the menu......");   /*按任一键进入主菜单*/
 getch();    /*从键盘读取一个字符,但不显示于屏幕*/
 clrscr();   /*清屏*/
 printf("********************************************************************************\n");
 printf("\t\t                Welcome to\n");
 printf("\n\t\t      The student score manage system\n");
 printf("*************************************MENU***************************************\n");
 printf("\t\t\t1. Enter the record\n");            /*输入学生成绩记录*/
 printf("\t\t\t2. Print the record\n");            /*显示*/
 printf("\t\t\t3. Search record on name\n");       /*寻找*/
 printf("\t\t\t4. Delete a record\n");             /*删除*/
 printf("\t\t\t5. Sort to make new a file\n");     /*排序*/
 printf("\t\t\t6. Insert record to list\n");       /*插入*/
 printf("\t\t\t7. Save the file\n");               /*保存*/
 printf("\t\t\t8. Load the file\n");               /*读取*/
 printf("\t\t\t9. Quit\n");                       /*退出*/
 printf("\n\t\t             Made by Hu Haihong.\n");
 printf("********************************************************************************\n");
 printf("\t\t\t\t%d\\%d\\%d\n",d.da_year,d.da_mon,d.da_day);   /*显示当前系统日期*/
 do{
    printf("\n\t\t\tEnter your choice(1~9):");  
    scanf("%d",&n);
   }while(n<1||n>9);    /*如果选择项不在1~9之间则重输*/
   return(n);           /*返回选择项，主函数根据该数调用相应的函数*/
}

/*输入函数*/
STUDENT *create()
{int i,s;
 STUDENT *head=NULL,*p;  /* 定义函数.此函数带回一个指向链表头的指针*/
 clrscr();
 for(;;)
   {p=(STUDENT *)malloc(LEN);  /*开辟一个新的单元*/
    if(!p)   /*如果指针p为空*/
      {printf("\nOut of memory.");   /*输出内存溢出*/
       return (head);  /*返回头指针,下同*/
      }
    printf("Enter the num(0:list end):"); 
    scanf("%s",p->num);
    if(p->num[0]=='0') break;    /*如果学号首字符为0则结束输入*/
    printf("Enter the name:");
    scanf("%s",p->name);
    printf("Please enter the %d scores\n",3);  /*提示开始输入成绩*/
    s=0;                /*计算每个学生的总分，初值为0*/
    for(i=0;i<3;i++)    /*3门课程循环3次*/
      {
       do{
      printf("score%d:",i+1);
      scanf("%d",&p->score[i]);
      if(p->score[i]<0 || p->score[i]>100)   /*确保成绩在0~100之间*/
      printf("Data error,please enter again.\n");
     }while(p->score[i]<0 || p->score[i]>100);
     s=s+p->score[i];   /*累加各门成绩*/
      }
      p->sum=s;     /*将总分保存*/
      p->average=(float)s/3;  /*先用强制类型转换将s转换成float型,再求平均值*/
      p->order=0;             /*未排序前此值为0*/
      p->next=head;           /*将头结点做为新输入结点的后继结点*/
      head=p;                 /*新输入结点为新的头结点*/
   }
   return(head);  
}

/* 显示全部记录函数*/
void print(STUDENT *head)
{int i=0;     /* 统计记录条数*/
 STUDENT *p;  /*移动指针*/
 clrscr();
 p=head;      /*初值为头指针*/
 printf("\n************************************STUDENT************************************\n");
 printf("-------------------------------------------------------------------------------\n");
 printf("| Rec |   Num   |   Name   |  Sc1  |  Sc2  |  Sc3  |  Sum  |   Ave   | Order |\n");
 printf("-------------------------------------------------------------------------------\n");
 while(p!=NULL)
   {
    i++;
    printf("| %3d |  %4s   |   %-4s   |  %3d  |  %3d  |  %3d  |  %3d  |  %4.2f  |  %-5d|\n", 
    i, p->num,p->name,p->score[0],p->score[1],p->score[2],p->sum,p->average,p->order);
    p=p->next;
   }
 printf("-------------------------------------------------------------------------------\n");
 printf("**************************************END**************************************\n");
}

/*查找记录函数*/
void search(STUDENT *head)
{STUDENT *p;    /*  移动指针*/
 char s[5];     /*存放姓名用的字符数组*/
 clrscr();
 printf("Please enter name for searching.\n");
 scanf("%s",s);
 p=head;    /*将头指针赋给p*/
 while(strcmp(p->name,s) && p != NULL)  /*当记录的姓名不是要找的，或指针不为空时*/
   p=p->next;     /*移动指针，指向下一结点*/
   if(p!=NULL)         /*如果指针不为空*/
   {printf("\n*************************************FOUND************************************\n");
    printf("-------------------------------------------------------------------------------\n");
    printf("|     Num    |    Name    |  sc1  |  sc2  |  sc3  |  Sum  |   Ave   | Order |\n");
    printf("-------------------------------------------------------------------------------\n");
    printf("|     %4s   |    %4s    |  %3d  |  %3d  |  %3d  |  %3d  |  %4.2f  |  %-5d|\n",
    p->num,p->name,p->score[0],p->score[1],p->score[2],p->sum,p->average,p->order);
    printf("-------------------------------------------------------------------------------\n");
    printf("***************************************END**************************************\n");
    }
   else
     printf("\nThere is no num %s student on the list.\n",s);   /*显示没有该学生*/
}

/*删除记录函数*/
STUDENT *delete(STUDENT *head)
{int n;
 STUDENT *p1,*p2;  /*p1为查找到要删除的结点指针，p2为其前驱指针*/
 char c,s[6];     /*s[6]用来存放学号,c用来输入字母*/
 clrscr();
 printf("Please enter the deleted num: ");
 scanf("%s",s);
 p1=p2=head;    /*给p1和p2赋初值头指针*/
 while(strcmp(p1->num,s) && p1 != NULL)   /*当记录的学号不是要找的，或指针不为空时*/
   {p2=p1;            /*将p1指针值赋给p2作为p1的前驱指针*/
    p1=p1->next;      /*将p1指针指向下一条记录*/
   }
 if(strcmp(p1->num,s)==0)  /*学号找到了*/
   {printf("**************************************FOUND************************************\n");
    printf("-------------------------------------------------------------------------------\n");
    printf("|     Num    |    Name    |  sc1  |  sc2  |  sc3  |  Sum  |   Ave   | Order |\n");
    printf("-------------------------------------------------------------------------------\n");
    printf("|     %4s   |    %4s    |  %3d  |  %3d  |  %3d  |  %3d  |  %4.2f  |  %-5d|\n",
    p1->num,p1->name,p1->score[0],p1->score[1],p1->score[2],p1->sum,p1->average,p1->order);
    printf("-------------------------------------------------------------------------------\n");
    printf("***************************************END**************************************\n");
    printf("Are you sure to delete the student Y/N ?"); /*提示是否要删除,输入Y删除,N则退出*/
    for(;;)
      {scanf("%c",&c);
       if(c=='n'||c=='N') break;  /*如果不删除,则跳出本循环*/
       if(c=='y'||c=='Y')
         {
          if(p1==head)       /*若p1==head，说明被删结点是首结点*/
          head=p1->next;     /*把第二个结点地址赋予head*/
        else
          p2->next=p1->next;  /*否则将一下结点地址赋给前一结点地址*/
          n=n-1;
          printf("\nNum %s student have been deleted.\n",s);
          printf("Don't forget to save.\n");break;  /*删除后就跳出循环*/
         }
      }
    }
  else
    printf("\nThere is no num %s student on the list.\n",s);  /*找不到该结点*/
 return(head);
}

/*排序函数*/
STUDENT *sort(STUDENT *head)
{int i=0;                       /*保存名次*/