C语言选课系统案例

#include<stdio.h>
#include<stdlib.h>
int N1,N2,kk1,kk2,kk3;
struct couse * head1;
struct student * head2;
struct couse//课程信息结构体
{
    int num1;
    char name1[20];
    int score;
    int nelepeo;//课程已选人数
    int Melepeo;//课程人数上限
    struct couse * next;
};
struct student//学生信息结构体
{
    int num2;
    char name2[20];
    int nelenum[50];//已选课程编号
    int nelen;//已选课程数量
    struct student * next;
};
void Ms()
{
    for(kk1=0;kk1<1100;kk1++)
                for(kk2=0;kk2<1200;kk2++)
                    for(kk3=0;kk3<1200;kk3++);
}
void keyboardc()//录入课程子函数(从键盘录入)
{
struct couse *p1,*p2;
N1=0;
p1=p2=(struct couse*)malloc(sizeof(struct couse));
printf("课程编号\t课程名称\t学分\t课程人数上限\n");
scanf("%d%s%d%d",&p1->num1,p1->name1,&p1->score,&p1->Melepeo);
p1->nelepeo=0;
head1=NULL;
while(p1->num1!=0)
{
    N1=N1+1;
    if(N1==1)head1=p1;
    else p2->next=p1;
    p2=p1;
    p1=(struct couse * )malloc(sizeof(struct couse));
    scanf("%d%s%d%d",&p1->num1,p1->name1,&p1->score,&p1->Melepeo);
    p1->nelepeo=0;
}
p2->next=NULL;
}
void filec()//录入键盘子函数(从文件录入)
{
    FILE * fp;
    char filepath[20];
    struct couse *p1,*p2;
    N1=0;
    printf("输入要读入的文件路径:");
    getchar();
    gets(filepath);
    if((fp=fopen(filepath,"r"))==NULL)
    {
        printf("找不到%s文件!\n",filepath);
        exit(0);
    }
    p1=p2=(struct couse*)malloc(sizeof(struct couse));
    fscanf(fp,"%d%s%d%d%d",&p1->num1,p1->name1,&p1->score,&p1->nelepeo,&p1->Melepeo);
    head1=NULL;
    while(!feof(fp))
    {
        N1=N1+1;
        if(N1==1)head1=p1;
        else p2->next=p1;
        p2=p1;
        p1=(struct couse * )malloc(sizeof(struct couse));
        fscanf(fp,"%d%s%d%d%d",&p1->num1,p1->name1,&p1->score,&p1->nelepeo,&p1->Melepeo);
    }
    p2->next=NULL;
}
void inputc()//录入课程主函数
{
    int i;
    printf("\t\t\t录入课程信息\n");
    printf("\n1.从键盘录入\n");
    printf("2.从文件录入\n");
    printf("3.返回主菜单\n");
    printf("请选择(1~3):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):keyboardc();break;
    case(2):filec();break;
    case(3):break;
    }
}
void insertc(struct couse *incouse)//课程管理子函数(增加课程)
{
    struct couse *p0,*p1,*p2;
    p1=head1;
    p0=incouse;
    if(head1==NULL)
    {
        head1=p0;
        p0->next=NULL;
    }
    else
    {
        while((p0->num1 > p1->num1) && (p1->next!=NULL))
        {
            p2=p1;
            p1=p1->next;
        }
        if(p0->num1 <= p1->num1)
        {
            if(head1==p1) head1=p0;
            else p2->next=p0;
            p0->next=p1;
        }
        else
        {
            p1->next=p0;
            p0->next=NULL;
        }
    }
    N1=N1+1;
}
void delc(int num1)//课程管理子函数(删除课程)
{
    struct couse *p1,*p2;
    if(head1==NULL)
    {
        printf("\n没有课程,无法删除!\n");
        goto end;
    }
    p1=head1;
    while(num1!=p1->num1 && p1->next!=NULL)
    {
        p2=p1;
        p1=p1->next;
    }
    if(num1==p1->num1)
    {
        if(p1==head1) head1=p1->next;
        else p2->next=p1->next;
        printf("已删除该编号课程!\n");
        N1=N1-1;
    }
    else printf("无该编号的课程!\n");
    end:;
}
void managementc()//课程管理主函数
{
    struct couse * incouse;
    int i,num1;
    printf("\t\t\t课程管理\n");
    printf("1.新增课程\n");
    printf("2.删除课程\n");
    printf("3.返回主菜单\n");
    printf("请选择(1~3):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):
        {
            incouse=(struct couse *)malloc(sizeof(struct couse));
            printf("课程编号\t课程名称\t学分\t课程人数上限\n");
            scanf("%d%s%d%d",&incouse->num1,incouse->name1,&incouse->score,&incouse->Melepeo);
            incouse->nelepeo=0;
            insertc(incouse);
            break;
        }
    case(2):
        {
            printf("请输入要删除课程的编号:\n");
            scanf("%d",&num1);
            delc(num1);
            break;
        }
    case(3):break;
    }
}
void keyboards()//录入学生信息子函数（从键盘录入）
{
    int i;
    struct student *p1,*p2;
    N2=0;
    p1=p2=(struct student *)malloc(sizeof(struct student));
    printf("学生学号\t学生姓名\n");
    scanf("%d%s",&p1->num2,p1->name2);
    p1->nelen=0;
    for(i=0;i<20;i++) p1->nelenum[i]=0;
    head2=NULL;
    while(p1->num2!=0)
    {
        N2=N2+1;
        if(N2==1)head2=p1;
        else p2->next=p1;
        p2=p1;
        p1=(struct student * )malloc(sizeof(struct student));
        scanf("%d%s",&p1->num2,p1->name2);
        p1->nelen=0;
        for(i=0;i<20;i++) p1->nelenum[i]=0;
    }
    p2->next=NULL;
}
void files()//录入学生信息子函数（从文件录入）
{
    int i=0;
    FILE * fp;
    char filepath[20];
    struct student *p1,*p2;
    N2=0;
    printf("输入要读入的文件路径:");
    getchar();
    gets(filepath);
    if((fp=fopen(filepath,"r"))==NULL)
    {
        printf("找不到%s文件!\n",filepath);
        exit(0);
    }
    p1=p2=(struct student*)malloc(sizeof(struct student));
    fread(p1,sizeof(struct student),1,fp);
    head2=NULL;
    while(!feof(fp))
    {
        i=0;
        N2=N2+1;
        if(N2==1)head2=p1;
        else p2->next=p1;
        p2=p1;
        p1=(struct student * )malloc(sizeof(struct student));
        fread(p1,sizeof(struct student),1,fp);
    }
    p2->next=NULL;
}
void inputs()//录入学生信息主函数
{
    int i;
    printf("\t\t\t录入学生信息\n");
    printf("\n1.从键盘录入\n");
    printf("2.从文件录入\n");
    printf("3.返回主菜单\n");
    printf("请选择(1~3):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):keyboards();break;
    case(2):files();break;
    case(3):break;
    }
}
void inserts(struct student * incouse)//学生信息管理子函数(填加学生信息)
{
    struct student *p0,*p1,*p2;
    p1=head2;
    p0=incouse;
    if(head2==NULL)
    {
        head2=p0;
        p0->next=NULL;
    }
    else
    {
        while((p0->num2 > p1->num2) && (p1->next!=NULL))
        {
            p2=p1;
            p1=p1->next;
        }
        if(p0->num2 <= p1->num2)
        {
            if(head2==p1) head2=p0;
            else p2->next=p0;
            p0->next=p1;
        }
        else
        {
            p1->next=p0;
            p0->next=NULL;
        }
    }
    N2=N2+1;
}
void dels(int num2)//学生信息管理子函数（删除学生信息)
{
    struct student *p1,*p2;
    if(head2==NULL)
    {
        printf("\n没有该学生信息,无法删除!\n");
        goto end;
    }
    p1=head2;
    while(num2!=p1->num2 && p1->next!=NULL)
    {
        p2=p1;
        p1=p1->next;
    }
    if(num2==p1->num2)
    {
        if(p1==head2) head2=p1->next;
        else p2->next=p1->next;
        printf("已删除该学生信息!\n");
        N2=N2-1;
    }
    else printf("无该学号的学生!\n");
    end:;
}
void managements()//学生信息管理主函数
{
    struct student * incouse;
    int i,num2;
    printf("\t\t\t学生信息管理\n");
    printf("1.新增学生信息\n");
    printf("2.删除学生信息\n");
    printf("3.返回主菜单\n");
    printf("请选择(1~3):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):
        {
            incouse=(struct student *)malloc(sizeof(struct student));
            incouse->nelen=0;
            incouse->nelenum[0]=0;
            printf("学生学号\t学生姓名\n");
            scanf("%d%s",&incouse->num2,incouse->name2);
            inserts(incouse);
            break;
        }
    case(2):
        {
            printf("请输入要删除学生的学号:\n");
            scanf("%d",&num2);
            dels(num2);
            break;
        }
    case(3):break;
    }
}
void elect(struct student * s)//选课
{
    struct couse * p;
    int num1,i;
    printf("请输入要选课的编号:\n");
    scanf("%d",&num1);
    for(i=0;s->nelenum[i]!=0;i++);
    s->nelenum[i]=num1;
    (s->nelen)++;
    p=head1;
    while(p->num1!=num1) p=p->next;
    (p->nelepeo)++;
}
void cheak()//学生选课子函数(查询可选课程)
{
    char e;
    struct couse * c;
    struct student * s;
    int num2,i,j=0,t=0;
    printf("请输入你的学号:");
    scanf("%d",&num2);
    s=head2;
    while(s->num2!=num2 && s->next!=NULL) s=s->next;
    if(s->num2!=num2)
    {
        printf("不存在你的信息,请进入主菜单录入你的信息!\n");
        goto end;
    }
    c=head1;
    printf("你的可选课程编号:\n");
    while(c!=NULL)
    {
        for(t=0,i=0;s->nelenum[i]!=0;i++)
        {
            if(c->num1==s->nelenum[i]) t=1;
        }
        if(t==0 && (c->nelepeo!=c->Melepeo))
        {
            printf("%d\n",c->num1);
            j++;
        }
        c=c->next;
    }
    if(j==0)
    {
        printf("你已选完所有课程，无法再多选!\n");
        goto end;
    }
    printf("选课(y/n)?:\n");
    getchar();
    e=getchar();
    i=0;
    while(e=='y')
    {
        elect(s);
        printf("继续选课(y/n)?:\n");
        getchar();
        e=getchar();
    }
    end:;
}
void back(struct student * p)//退课
{
    struct couse * p1;
    int num1,i,j;
    printf("请输入你要退掉的课程编号:\n");
    scanf("%d",&num1);
    p1=head1;
    while(p1->num1!=num1) p1=p1->next;
    for(i=0;p->nelenum[i]!=num1;i++);
    for(j=i;p->nelenum[j]!=0;j++) p->nelenum[j]=p->nelenum[j+1];
    p->nelenum[--j]=0;
    (p1->nelepeo)--;
    printf("退课成功!\n");
}
void hcheak()//学生选课子函数（查询已选课程)
{
    char c;
    struct couse * p0;
    struct student * p;
    int num2,i,f=0;
    printf("请输入学号:\n");
    scanf("%d",&num2);
    p=head2;
    while(p->num2!=num2 && p!=NULL) p=p->next;
    if(p==NULL)
    {
        printf("不存在你的信息,请回主菜单录入信息:\n");
        goto end;
    }
    printf("已选课程编号:\n");
    if(p->nelenum[0]==0)
    {
        printf("你还没选课!\n");
        goto end;
    }
    for(i=0;p->nelenum[i]!=0;i++)
    {
        printf("%d\n",p->nelenum[i]);
        p0=head1;
        while(p0->num1!=p->nelenum[i]) p0=p0->next;
        f=f+p0->score;
    }
    printf("总学分:%d\n",f);
    printf("是否进行退课(y/n)?");
    getchar();
    c=getchar();
    while(c=='y')
    {
        back(p);
        printf("继续退课(y/n)?");
        getchar();
        c=getchar();
        (p->nelen)--;
    }
    end:;
}
void elective()//学生选课主函数
{
    int i;
    printf("\t\t\t学生选课\n");
    printf("1.查询可选课程\n");
    printf("2.查询已选课程\n");
    printf("3.返回主菜单\n");
    printf("请输入(1~3):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):cheak();break;
    case(2):hcheak();break;
    case(3):break;
    }
}
void listc()//输出课程信息
{
    struct couse * p;
    p=head1;
    printf("课程编号  课程名称  学分  课程已选人数  课程人数上限\n");
    while(p!=NULL)
    {
        printf("%-8d%10s%6d%8d%12d\n",p->num1,p->name1,p->score,p->nelepeo,p->Melepeo);
        p=p->next;
    }
}
void lists()//输出学生信息
{
    struct student * p;
    p=head2;
    printf("学生学号  学生姓名  已选课程数量\n");
    while(p!=NULL)
    {
        printf("%-4d %10s %6d\n",p->num2,p->name2,p->nelen);
        p=p->next;
    }
}
void intoc()//存储课程信息
{
    FILE * fp;
    struct couse * p;
    char filepath[30];
    printf("输入课程信息要保存的文件路径:");
    getchar();    
    gets(filepath);
    if((fp=fopen(filepath,"w"))==NULL)
    {
        printf("\n保存失败!");
        exit(0);
    }
    p=head1;
    while(p!=NULL)
    {
        fprintf(fp,"%d %s %d %d %d\n",p->num1,p->name1,p->score,p->nelepeo,p->Melepeo);
        p=p->next;
    }
    fclose(fp);
    printf("课程信息已保存在%s中!\n",filepath);
}
void intos()//存储学生信息
{
    FILE * fp;
    struct student * p;
    char filepath[30];
    printf("输入学生信息要保存的文件路径:");
    getchar();    
    gets(filepath);
    if((fp=fopen(filepath,"w"))==NULL)
    {
        printf("\n保存失败!");
        exit(0);
    }
    p=head2;
    while(p!=NULL)
    {
        fwrite(p,sizeof(struct student),1,fp);
        p=p->next;
    }
    fclose(fp);
    printf("学生信息已保存在%s中!\n",filepath);
}
void into()//存储信息
{
    int i;
    printf("1.存储课程信息\n");
    printf("2.存储学生信息\n");
    printf("3.返回主菜单\n");
    printf("请输入(1~3)\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):intoc();break;
    case(2):intos();break;
    case(3):break;
    }    
}
void store()//信息主函数
{
    int i;
    printf("\t\t系统信息查看及存储\n");
    printf("1.查看课程信息\n");
    printf("2.查看学生信息\n");
    printf("3.存储信息\n");
    printf("4.返回主菜单\n");
    printf("请输入(1~4):\n");
    scanf("%d",&i);
    switch(i)
    {
    case(1):listc();break;
    case(2):lists();break;
    case(3):into();break;
    case(4):break;
    }
}
int main()//主函数
{
    int i;
    start:
    printf("\n\t\t\t欢迎使用学生选课系统!\n");
    printf("菜单:\n");
    printf("1.录入课程信息\n");
    printf("2.课程管理\n");
    printf("3.录入学生信息\n");
    printf("4.学生信息管理\n");
    printf("5.学生选课\n");
    printf("6.系统信息查看及存储\n");
    printf("7.退出系统\n");
    printf("\n请输入菜单选项(1~7):\n");
    scanf("%d",&i);
    if(i<1 || i>7)
    {
        printf("输入错误,请重输:\n");
        goto start;
    }
    switch(i)
    {
    case(1):
        {
            system("cls");
            inputc();
            goto start;
            break;
        }
    case(2):
        {
            system("cls");
            managementc();
            goto start;
            break;
        }
    case(3):
        {
            system("cls");
            inputs();
            goto start;
            break;
        }
    case(4):
        {
            system("cls");
            managements();
            goto start;
            break;
        }
    case(5):
        {
            system("cls");
            elective();
            goto start;
            break;
        }
    case(6):
        {
            system("cls");
            store();
            goto start;
            break;
        }
    case(7):
        {
            system("cls");
            printf("感谢使用本系统!\n\n再见!\n");
        }
    }
    return(0);
}