学生成绩管理系统

//学生成绩管理系统
/*（1）任务描述
设计一个学生成绩管理系统，实现对学生成绩的动态管理，实现对学生成绩的输入，显示，删除，查找，插入，最佳，保存，计算，排序等主要功能。
（2）功能要求
1、每一条记录包括一个学生的学号、姓名、3门课成绩、平均成绩。
2、输入功能：可以一次完成若干条记录的输入。
3、显示功能：完成全部学生记录的显示。
4、查找功能：完成按姓名查找学生记录，并显示。
5、排序功能：按学生平均成绩进行排序。
6、插入功能：按平均成绩高低插入一条学生记录
7、删除功能：如果输入错误，可以删除学生记录；
8、退出。*/

#include
#include
#include
#define SIZE_NAME 20
#define SIZE_ID 20
int Record = 0;

typedef struct 
{
    char name[SIZE_NAME];
    char id[SIZE_ID];
    int a, b, c;
    int ava;
}pInfo;

typedef struct node 
{
    pInfo people;
    struct node *next;
}linkList;

int menu()//菜单，选择数字
{
    int chus;
    printf("学生信息系统\n\n");
    printf("1.创建学生信息\n");
    printf("2.显示学生信息\n");
    printf("3.查询学生信息\n");
    printf("4.修改学生信息\n");
    printf("5.添加学生信息\n");
    printf("6.删除学生信息\n");
    printf("7.排序学生成绩\n");
    printf("8.退出\n");
    printf("请输入数字:");
    scanf("%d", &chus);
    return chus;
}

int create(linkList *head)//创建
{
    linkList *s, *p;
    p = head;
    printf("请输入学号 姓名 三科成绩,输入end结束\n");
    while (1)
    {
        s = (linkList*)malloc(sizeof(linkList));
        scanf("%s", s->people.id);
        if (!strcmp(s->people.id, "end")) 
        {
            return 0;
        }
        scanf("%s", s->people.name);
        scanf("%d", &s->people.a);
        scanf("%d", &s->people.b);
        scanf("%d", &s->people.c);
        s->people.ava = (s->people.a + s->people.b + s->people.c) / 3;//三科的成绩相加除以3，求平均数
        s->next = p->next;
        p->next = s;
        p = s;
        Record++;
    }
    return 0;
}

int display(linkList *head)//显示关键的词
{
    int i;
    linkList *p;
    p = head;
    p = p->next;
    printf("\t\t\t学生信息\n");
    printf("--------------------------------------------------------------------------------\n");
    printf("\t\t学号\t\t姓名\t\t\t平均成绩\n");
    printf("--------------------------------------------------------------------------------\n");
    for (i = 0; i < Record; i++, p = p->next)
    {
        printf("%20s\t", p->people.id);
        printf("%10s\t", p->people.name);
        printf("%20d\n", p->people.ava);
    }

    return 0;
}

int search(linkList *head, char *info)//查找
{
    int i;
    linkList *p;
    p = head;
    p = p->next;
    for (i = 0; i < Record; i++, p = p->next) 
    {
        if ((!strcmp(p->people.id, info)) || (!strcmp(info, p->people.name))) 
        {
            return i;
        }
    }
    return -1;
}

int modify(linkList *head, char *pid)//修改
{
    int i;
    linkList *p;
    p = head;
    p = p->next;
    for (i = 0; i < search(head, pid); i++)
    {
        p = p->next;
    }
    printf("请输入新信息:\n");
    scanf("%s", p->people.id);
    scanf("%s", p->people.name);
    scanf("%d", &p->people.a);
    scanf("%d", &p->people.b);
    scanf("%d", &p->people.c);
    p->people.ava = (p->people.a + p->people.b + p->people.c) / 3;
    return 0;
}

int add2(linkList *head, char *pid)//添加学生信息
{
    int i;
    linkList *p, *s;
    p = head;
    p = p->next;
    s = (linkList*)malloc(sizeof(linkList));
    while (p->next != NULL) 
    {
        p = p->next;
    }
    printf("请输入需要添加的姓名和成绩:\n");
    strcpy(s->people.id, pid);
    scanf("%s", s->people.name);
    scanf("%d", &s->people.a);
    scanf("%d", &s->people.b);
    scanf("%d", &s->people.c);
    s->people.ava = (s->people.a + s->people.b + s->people.c) / 3;
    if (search(head, s->people.id) == -1) 
    {
        s->next = p->next;
        p->next = s;
        Record++;
    }
    else 
    {
        printf("学号重复了\n");
    }
    sort(head, 0);
    return 0;
}

int delt(linkList *head, char *info)//双端测试
{
    int i, n;
    linkList *p, *s;
    p = head;
    n = search(head, info);
    if (-1 == n) {
        printf("没有找到\n");
        return 0;
    }
    for (i = 0; i < n; i++)
    {
        p = p->next;
    }
    p->next = p->next->next;
    Record--;
    return 0;
}
int compare(int ava1, int ava2)
{
    if (ava1 < ava2)
    {
        return 1;
    }
    return 0;
}

int sort(linkList *head, int boolean)//排序，1升序，0降序
{
    linkList *p, *pre;
    pInfo temp;
    if (boolean) 
    {
        for (p = head->next; p != NULL; p = p->next) 
        {
            for (pre = p->next; pre != NULL; pre = pre->next)
            {
                if (0 == compare(p->people.ava, pre->people.ava))
                {
                    temp = p->people;
                    p->people = pre->people;
                    pre->people = temp;
                }
            }
        }
    }
    else {
        for (p = head->next; p != NULL; p = p->next)
        {
            for (pre = p->next; pre != NULL; pre = pre->next)
            {
                if (1 == compare(p->people.ava, pre->people.ava)) 
                {
                    temp = p->people;
                    p->people = pre->people;
                    pre->people = temp;
                }
            }
        }
    }
    return 0;
}
int main()
{
    linkList head, *p;
    char info[SIZE_ID];
    int temp, chus, i;
    head.next = NULL;
    while (1)
    {
        switch (menu()) 
        {
        case 1:
            create(&head);
            break;
        case 2:
            display(&head);
            break;
        case 3:
            printf("请输入需要查询的学号或姓名: ");
            scanf("%s", info);
            p = &head;
            p = p->next;
            for (i = 0; i < search(&head, info); i++)
            {
                p = p->next;
            }
            printf("搜索到:\n");
            printf("\t\t\t学生信息\n");
            printf("--------------------------------------------------------------------------------\n");
            printf("\t学号\t姓名\t平均成绩\n");
            printf("--------------------------------------------------------------------------------\n");
            printf("%s\t", p->people.id);
            printf("%s\t", p->people.name);
            printf("%d\n", p->people.ava);
            break;
        case 4:
            printf("请输入需要修改的学号: ");
            scanf("%s", info);
            modify(&head, info);
            break;
        case 5:
            printf("请输入需要添加的学号: ");
            scanf("%s", info);
            add2(&head, info);
            break;
        case 6:
            printf("请输入需要删除的学号或姓名: ");
            scanf("%s", info);
            delt(&head, info);
            break;
        case 7:
            printf("请输入1或0:\n\t1:升序\n\t0:降序\n");
            scanf("%d", &temp);
            sort(&head, temp);
            break;
        case 8:
            exit(0);
            break;
        default:
            printf("输错了，再来一次\n");
        }
        system("pause");
        system("cls");
    }
    system("pause");
    return 0;
}

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