关于#c语言#的问题：修改此程序，**使其具有多个班级**，并能进行**班级内**单科成绩排名#include <stdio.h>

修改此程序，使其具有多个班级，并能进行班级内单科成绩排名

#include 
#include //包含了控制台窗口操作相关的函数
#include 
#define LEN sizeof(struct Student)// 定义结构体类型所占的内存大小
struct Student// 定义结构体类型
{
    char name[10];        
    char number[20];                     
    int C_Language;            
    int Math;                
    int English;    
    struct Student* next;     // 存储下一个学生的地址
};
struct Student* head = NULL;// 定义头节点指针
struct Student* end = NULL;// 定义尾节点指针
 void Menu()// 定义菜单函数
 {
     void Menu();// 声明菜单函数
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    system("cls"); // 清空控制台窗口内容
    printf("1.学生信息录入\n");
    printf("2.学生单个成绩查询\n");
    printf("3.查询全部学生成绩\n");
    printf("4.修改学生信息\n");
    printf("5.删除学生信息\n");
    printf("6.学生单科成绩录入\n"); 
    printf("7.退出系统\n");

    int choice;
    printf("请选择要使用的功能：\n");
    loop:
    scanf("%d",&choice);
    switch (choice)
    {
        case 1:
            Add();
            Menu();
        case 2:
            View();
            Menu();
        case 3:
            ViewAll();
            Menu();
        case 4:
            Repair();
            Menu();
        case 5:
            Delete();
            Menu();
        case 6:
            AddOne();
            Menu();
        case 7:
            exit(0);
            default:
                printf("输入有误，请重新选择：");
                break;
    }
} 
 
void Add()
{
    system("cls");
    int count;
    printf("请输入要录入信息的个数：");
    scanf("%d",&count);
    struct Student *s1,*s2,*temp;
    s1=s2=(struct Student*)malloc(LEN);
    if(head==NULL)
    {
        head = s1;
    }
    else
    {
        end->next = s1 ;
    }
    int i = 1;    
    while(count>0)
    {
        printf("请输入第%d位学生信息：\n",i++);
        printf("姓名：\n");
        scanf("%s",&s1->name);
        printf("学号：\n");
        scanf("%s",&s1->number);
        printf("C语言成绩：\n");
        scanf("%d",&s1->C_Language);
        printf("数学成绩:\n");
        scanf("%d",&s1->Math);
        printf("英语成绩:\n");
        scanf("%d",&s1->English);
        count--;
        s2->next=s1;
        s2=s1;
        s1=(struct Student*)malloc(LEN);
        printf("添加成功！\n");
        system("pause");
        system("cls");
    }
    s2->next= NULL;
    end = s2;
    printf("全部添加成功！\n");
    system("pause");
}
void View()
{
    system("cls");
    struct Student *VS;
    printf("输入要查询信息的学生学号：\n");
    char num[10];
    int flag=1;
    scanf("%s",&num);
    for(VS=head;VS!=NULL;)
    {
        if(strcmp(VS->number,num)==0)
        {
            printf("成功找到！\n");
            printf("姓名：%s\t学号：%s\t\n",VS->number,VS->name);
            printf("C语言：%d\t数学:%d\t英语：%d",VS->C_Language,VS->Math,VS->English);
            flag=0;
            break;
        }
        VS=VS->next;
    }
    if(flag)
    {
        printf("不好意思，未找到！\n");
    }
    system("pause");
}
void ViewAll()
{
    system("cls");
    struct Student *VA;
    if(head!=NULL)
    {
        printf("所有学生成绩如下：\n");
        for(VA=head;VA!=NULL;)
        {
            printf("姓名：%s\t学号：%s\t\n",VA->name,VA->number);
            printf("C语言：%d\t数学:%d\t英语：%d\n",VA->C_Language,VA->Math,VA->English);
            VA=VA->next; 
        }
        printf("所有不及格科目超过两科的学生名单如下:\n");
        for(VA=head;VA!=NULL;)
        {
             int lostNum = 0;
            if(VA->C_Language < 60)
            {
                lostNum++;
            }
            if(VA->Math< 60)
            {
                lostNum++;
            }
            if(VA->English< 60)
            {
                lostNum++;
            }
            if(lostNum > 1)
            {
                printf("姓名：%s\t\n",VA->name);
            }
             VA = VA->next;
        }

    }
    else
    {
        printf("该系统中还未录入信息");
    }
    system("pause");
}
void Repair()
{
    system("cls");
    struct Student *RS;
    char num[10];
    int flag = 1;
    printf("输入要修改成绩学生的学号：\n");
    scanf("%s",num);
    for(RS=head;RS!=NULL;)
    {
        if(strcmp(RS->number,num)==0)
        {
            printf("成功找到该学生");
            printf("姓名：%s\t学号：%s\t\n",RS->number,RS->name);
            printf("C语言：%d\t数学:%d\t英语：%d\n",RS->C_Language,RS->Math,RS->English);
            flag = 0;
            printf("姓名：\n");
            scanf("%s",&RS->name);
            printf("学号：\n");
            scanf("%s",&RS->number);
            printf("C语言成绩：\n");
            scanf("%d",&RS->C_Language);
            printf("数学成绩:\n");
            scanf("%d",&RS->Math);
            printf("英语成绩:\n");
            scanf("%d",&RS->English);
            printf("修改成功");
            system("pause");
        }
        RS=RS->next;
    }
    if(flag)
    {
        printf("输入信息有误，未查询到");
        system("pause");
    }
}
void Delete()
{
    system("cls");
    int flag =1;
    while(flag)
    {
        printf("请输入要删除的学生学号：");
        char num[10];
        scanf("%s",&num);
        struct Student * DS,*temp;
        for(DS=head;DS!=NULL;)
        {
            if(strcmp(DS->number,num)==0)
            {
                if(DS==head)
                {
                    head = DS->next;
                    flag = 0;
                    printf("删除成功！\n");
                    system("pause");
                }
                else
                {
                    flag = 0;
                    printf("删除成功！\n");
                    temp->next= DS->next;
                    free(DS);
                    system("pause");
                }
                break;
            }
            temp = DS;
            DS=DS->next;
        }
        if(flag)
        {
            printf("未找到该学生学号！\n");
            system("pause");
        } 
    }
}

 
 
void AddOne()
{
    system("cls");
    struct Student* DA =(struct Student*)malloc(sizeof(struct Student)); //修改1 
    DA->next = NULL; //修改，增加这一行
    int flag = 1;
    while (flag)
    {
        printf("请输入姓名：\n");
        scanf("%s", DA->name);
        printf("请输入学号：\n");
        scanf("%s", DA->number);
        printf("1.录入C语言成绩\n");
        printf("2.录入数学成绩\n");
        printf("3.录入英语成绩\n");
        int select;
        scanf("%d", &select);
        switch (select)
        {
        case 1:
            printf("请输入C语言成绩\n");
            scanf("%d", &DA->C_Language); //修改，增加 &
            break;
        case 2:
            printf("请输入数学成绩\n");
            scanf("%d", &DA->Math);//修改，增加 &
            break;
        case 3:
            printf("请输入英语成绩\n");
            scanf("%d", &DA->English);//修改，增加 &
            break;
        default:
            printf("输入错误，请重新输入\n");
            break;
        }
        printf("录入成功\n");
        flag = 0;
        struct Student* DB, * temp; //修改  DA改成DB
        //DA插入链表
        if (head == NULL)
            head = DA;
        else
        {
            for (DB = head; DB->next != NULL;){
                DB = DB->next;
            }
            DB->next = DA;
        }
        system("pause");
    }
}
int main()
{
    void Menu();
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    Menu();
    
}

基于最新版ChatGPT4的回答，望采纳!!!有其他问题也可以询问我哦、”(最新版更智能，功能更加强大)

要修改此程序以支持多个班级并进行班级内单科成绩排名，你可以对结构体和相应的函数进行一些调整。首先，为 Student 结构体添加一个表示班级的字段 classID。然后，在添加学生信息时添加班级字段。最后，实现一个新函数 Rank()，用于显示每个班级内的单科成绩排名。

以下是修改后的代码：

#include <stdio.h>
#include <windows.h>
#include <stdlib.h>
#include <string.h>

#define LEN sizeof(struct Student)

struct Student {
    char name[10];
    char number[20];
    int classID;
    int C_Language;
    int Math;
    int English;
    struct Student *next;
};

struct Student *head = NULL;
struct Student *end = NULL;

// 声明所有函数
void Menu();
void Add();
void View();
void Delete();
void Repair();
void ViewAll();
void AddOne();
void Rank();

int main() {
    Menu();
    return 0;
}

void Menu() {
    system("cls");
    printf("1.学生信息录入\n");
    printf("2.学生单个成绩查询\n");
    printf("3.查询全部学生成绩\n");
    printf("4.修改学生信息\n");
    printf("5.删除学生信息\n");
    printf("6.学生单科成绩录入\n");
    printf("7.班级内单科成绩排名\n");
    printf("8.退出系统\n");
int choice;
printf("请选择要使用的功能：\n");
scanf("%d", &choice);
switch (choice) {
    case 1:
        Add();
        Menu();
        break;
    case 2:
        View();
        Menu();
        break;
    case 3:
        ViewAll();
        Menu();
        break;
    case 4:
        Repair();
        Menu();
        break;
    case 5:
        Delete();
        Menu();
        break;
    case 6:
        AddOne();
        Menu();
        break;
    case 7:
        Rank();
        Menu();
        break;
    case 8:
        exit(0);
        break;
    default:
        printf("输入有误，请重新选择：");
        break;
}
}

// 在原有的 Add 函数中添加班级输入
void Add() {
    // ... 其他代码不变
    while (count > 0) {
        printf("请输入第%d位学生信息：\n", i++);
        printf("姓名：\n");
        scanf("%s", s1->name);
        printf("学号：\n");
        scanf("%s", s1->number);
        printf("班级：\n");  // 新增班级输入
        scanf("%d", &s1->classID);
        // ... 其他代码不变
    }
}

// 新增函数 Rank 用于显示每个班级内的单科成绩排名
void Rank() {
    system("cls");
    // 排序功能可以使用类似冒泡排序的算法进行排序
struct Student *p, *q;
struct Student temp;

printf("请选择要进行排名的科目：\n");
printf("1.C语言\n");
printf("2.数学\n");
printf("3.英语\n");
int choice;
scanf("%d", &choice);
for (p = head; p != NULL; p = p->next) {
    for (q = p->next; q != NULL; q = q->next) {
        int need_swap = 0;
        switch (choice) {
            case 1:
                if (p->C_Language < q->C_Language && p->classID == q->classID) {
                    need_swap = 1;
                }
                break;
            case 2:
                if (p->Math < q->Math && p->classID == q->classID) {
                    need_swap = 1;
                }
                break;
            case 3:
                if (p->English < q->English && p->classID == q->classID) {
                    need_swap = 1;
                }
                break;
            default:
                printf("输入有误，请重新选择：");
                break;
        }

        if (need_swap) {
            temp = *p;
            *p = *q;
            *q = temp;
            struct Student *temp_next = p->next;
            p->next = q->next;
            q->next = temp_next;
        }
    }
}
printf("按照班级和选择的科目进行排名：\n");
for (struct Student *r = head; r != NULL; r = r->next) {
    printf("姓名：%s\t学号：%s\t班级：%d\t", r->name, r->number, r->classID);
    switch (choice) {
        case 1:printf("C语言：%d\n", r->C_Language);
            break;
        case 2:
            printf("数学：%d\n", r->Math);
            break;
        case 3:
            printf("英语：%d\n", r->English);
            break;
        default:
            printf("输入有误，请重新选择：");
            break;
    }
}
system("pause");
}
//接下来，我们将修改Menu函数，增加一个选项用于进行班级内单科成绩排名：
void Menu() {
    ...
    printf("8.班级内单科成绩排名\n");
    ...
    case 8:
        RankBySubjectInClass();
        Menu();
    ...
}

运行结果如下（我这里排名只显示了排名、姓名和对应科目的成绩，如果需要显示全部信息，你在printf语句中添加上就可以了）：

完整代码：

#include <stdio.h>
#include <windows.h>//包含了控制台窗口操作相关的函数
#include <stdlib.h>
#define LEN sizeof(struct Student)// 定义结构体类型所占的内存大小
struct Student// 定义结构体类型
{
    char name[10];
    char number[20];
    int classId; //班级
    int C_Language;
    int Math;
    int English;
    struct Student* next;     // 存储下一个学生的地址
};
struct Student* head = NULL;// 定义头节点指针
struct Student* end = NULL;// 定义尾节点指针
void Menu()// 定义菜单函数
{
    void Menu();// 声明菜单函数
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    void Rank();
    system("cls"); // 清空控制台窗口内容
    printf("1.学生信息录入\n");
    printf("2.学生单个成绩查询\n");
    printf("3.查询全部学生成绩\n");
    printf("4.修改学生信息\n");
    printf("5.删除学生信息\n");
    printf("6.学生单科成绩录入\n");
    printf("7.班级内单科成绩排名\n");
    printf("8.退出系统\n");

    int choice;
    printf("请选择要使用的功能：\n");
loop:
    scanf("%d", &choice);
    switch (choice)
    {
    case 1:
        Add();
        Menu();
    case 2:
        View();
        Menu();
    case 3:
        ViewAll();
        Menu();
    case 4:
        Repair();
        Menu();
    case 5:
        Delete();
        Menu();
    case 6:
        AddOne();
        Menu();
    case 7:
        Rank();
        Menu();
    case 8:
        exit(0);
    default:
        printf("输入有误，请重新选择：");
        break;
    }
}

void Add()
{
    system("cls");
    int count;
    printf("请输入要录入信息的个数：");
    scanf("%d", &count);
    struct Student* s1, * s2, * temp;
    s1 = s2 = (struct Student*)malloc(LEN);
    if (head == NULL)
    {
        head = s1;
    }
    else
    {
        end->next = s1;
    }
    int i = 1;
    while (count > 0)
    {
        printf("请输入第%d位学生信息：\n", i++);
        printf("姓名：\n");
        scanf("%s", &s1->name);
        printf("学号：\n");
        scanf("%s", &s1->number);
        printf("班级：\n");
        scanf("%d", &s1->classId); //添加，录入班级
        printf("C语言成绩：\n");
        scanf("%d", &s1->C_Language);
        printf("数学成绩:\n");
        scanf("%d", &s1->Math);
        printf("英语成绩:\n");
        scanf("%d", &s1->English);
        count--;
        s2->next = s1;
        s2 = s1;
        s1 = (struct Student*)malloc(LEN);
        printf("添加成功！\n");
        system("pause");
        system("cls");
    }
    s2->next = NULL;
    end = s2;
    printf("全部添加成功！\n");
    system("pause");
}
void View()
{
    system("cls");
    struct Student* VS;
    printf("输入要查询信息的学生学号：\n");
    char num[10];
    int flag = 1;
    scanf("%s", &num);
    for (VS = head; VS != NULL;)
    {
        if (strcmp(VS->number, num) == 0)
        {
            printf("成功找到！\n");
            printf("姓名：%s\t学号：%s\t班级：%d\t\n", VS->number, VS->name,VS->classId); //修改，增加班级显示
            printf("C语言：%d\t数学:%d\t英语：%d", VS->C_Language, VS->Math, VS->English);
            flag = 0;
            break;
        }
        VS = VS->next;
    }
    if (flag)
    {
        printf("不好意思，未找到！\n");
    }
    system("pause");
}
void ViewAll()
{
    system("cls");
    struct Student* VA;
    if (head != NULL)
    {
        printf("所有学生成绩如下：\n");
        for (VA = head; VA != NULL;)
        {
            printf("姓名：%s\t学号：%s\t班级：%d\t\n", VA->name, VA->number,VA->classId); //增加班级显示
            printf("C语言：%d\t数学:%d\t英语：%d\n", VA->C_Language, VA->Math, VA->English);
            VA = VA->next;
        }
        printf("所有不及格科目超过两科的学生名单如下:\n");
        for (VA = head; VA != NULL;)
        {
            int lostNum = 0;
            if (VA->C_Language < 60)
            {
                lostNum++;
            }
            if (VA->Math < 60)
            {
                lostNum++;
            }
            if (VA->English < 60)
            {
                lostNum++;
            }
            if (lostNum > 1)
            {
                printf("姓名：%s\t\n", VA->name);
            }
            VA = VA->next;
        }

    }
    else
    {
        printf("该系统中还未录入信息");
    }
    system("pause");
}
void Repair()
{
    system("cls");
    struct Student* RS;
    char num[10];
    int flag = 1;
    printf("输入要修改成绩学生的学号：\n");
    scanf("%s", num);
    for (RS = head; RS != NULL;)
    {
        if (strcmp(RS->number, num) == 0)
        {
            printf("成功找到该学生");
            printf("姓名：%s\t学号：%s\t班级：%d\t\n", RS->number, RS->name,RS->classId); //增加班级显示
            printf("C语言：%d\t数学:%d\t英语：%d\n", RS->C_Language, RS->Math, RS->English);
            flag = 0;
            printf("姓名：\n");
            scanf("%s", &RS->name);
            printf("学号：\n");
            scanf("%s", &RS->number);
            printf("班级：\n");
            scanf("%d", &RS->classId);
            printf("C语言成绩：\n");
            scanf("%d", &RS->C_Language);
            printf("数学成绩:\n");
            scanf("%d", &RS->Math);
            printf("英语成绩:\n");
            scanf("%d", &RS->English);
            printf("修改成功");
            system("pause");
        }
        RS = RS->next;
    }
    if (flag)
    {
        printf("输入信息有误，未查询到");
        system("pause");
    }
}
void Delete()
{
    system("cls");
    int flag = 1;
    while (flag)
    {
        printf("请输入要删除的学生学号：");
        char num[10];
        scanf("%s", &num);
        struct Student* DS, * temp = head;
        for (DS = head; DS != NULL;)
        {
            if (strcmp(DS->number, num) == 0)
            {
                if (DS == head)
                {
                    head = DS->next;
                    flag = 0;
                    printf("删除成功！\n");
                    system("pause");
                }
                else
                {
                    flag = 0;
                    printf("删除成功！\n");
                    temp->next = DS->next;
                    free(DS);
                    system("pause");
                }
                break;
            }
            temp = DS;
            DS = DS->next;
        }
        if (flag)
        {
            printf("未找到该学生学号！\n");
            system("pause");
        }
    }
}



void AddOne()
{
    system("cls");
    struct Student* DA = (struct Student*)malloc(sizeof(struct Student)); //修改1 
    DA->next = NULL; //修改，增加这一行
    int flag = 1;
    while (flag)
    {
        printf("请输入姓名：\n");
        scanf("%s", DA->name);
        printf("请输入学号：\n");
        scanf("%s", DA->number);
        printf("请输入班级：\n");
        scanf("%d", &DA->classId);
        printf("1.录入C语言成绩\n");
        printf("2.录入数学成绩\n");
        printf("3.录入英语成绩\n");
        int select;
        scanf("%d", &select);
        switch (select)
        {
        case 1:
            printf("请输入C语言成绩\n");
            scanf("%d", &DA->C_Language); //修改，增加 &
            break;
        case 2:
            printf("请输入数学成绩\n");
            scanf("%d", &DA->Math);//修改，增加 &
            break;
        case 3:
            printf("请输入英语成绩\n");
            scanf("%d", &DA->English);//修改，增加 &
            break;
        default:
            printf("输入错误，请重新输入\n");
            break;
        }
        printf("录入成功\n");
        flag = 0;
        struct Student* DB, * temp; //修改  DA改成DB
        //DA插入链表
        if (head == NULL)
            head = DA;
        else
        {
            for (DB = head; DB->next != NULL;) {
                DB = DB->next;
            }
            DB->next = DA;
        }
        system("pause");
    }
}

//链表排序
struct Student* sort_list(struct Student* head, int sec)   //排序
{
    if (NULL == head)    //若链表为空则不用排序
    {
        return NULL;
    }
    if (NULL == head->next)  //若链表中只有一个数，则不用比较
    {
        //printf("min is head\n");
        return head;
    }


    struct Student* min_pre = NULL;
    struct Student* min = head;
    struct Student* tmp = head;
    struct Student* new_list = NULL;
    struct Student* tail_sort = NULL;

    while (head)
    {
        min = head;
        tmp = head;
        while (tmp->next)
        {
            if (sec == 1) //根据C语言成绩排序
            {
                if (min->C_Language < tmp->next->C_Language)
                {
                    min = tmp->next;
                    min_pre = tmp;
                }
            }
            else if (sec == 2) //根据math成绩排序
            {
                if (min->Math < tmp->next->Math)
                {
                    min = tmp->next;
                    min_pre = tmp;
                }
            }
            else if (sec == 3) //根据english排序
            {
                if (min->English < tmp->next->English)
                {
                    min = tmp->next;
                    min_pre = tmp;
                }
            }

            tmp = tmp->next;
        }
        if (min == head)
        {
            head = head->next;
        }
        else
        {
            min_pre->next = min->next;
            min->next = NULL;
        }
        if (NULL == new_list)    //按照尾插将最小的数组成新的链表
        {
            tail_sort = min;
            new_list = tail_sort;
        }
        else
        {
            tail_sort->next = min;
            tail_sort = min;
        }
    }
    head = new_list;
    return head;
}




void Rank()
{
    int sec;
    struct Student* tmp = 0;
    int rk = 1;
    int classId;
    int flag = 0;
    while (1)
    {
        rk = 1;
        flag = 0;
        printf("请输入要查询的班级：");
        scanf("%d", &classId);
        printf("1.按C语言成绩排序\n");
        printf("2.按Math成绩排序\n");
        printf("3.按English成绩排序\n");
        
        scanf("%d", &sec);
        if (sec >= 1 && sec <= 3)
        {
            head = sort_list(head, sec);
            //显示排名
            tmp = head;
            while (tmp)
            {
                if (tmp->classId == classId)
                {
                    if (sec == 1)
                        printf("%d %s %d\n", rk, tmp->name, tmp->C_Language);
                    else if (sec == 2)
                        printf("%d %s %d\n", rk, tmp->name, tmp->Math);
                    else if (sec == 3)
                        printf("%d %s %d\n", rk, tmp->name, tmp->English);
                    rk++;
                    flag = 1;
                }
                
                tmp = tmp->next;
            }
            if (flag == 0)
                printf("未找到该班级学生！\n");
        }
        else
            printf("输入错误\n");
        printf("1.继续查询\n");
        printf("0.结束查询\n");
        scanf("%d", &sec);
        if (sec == 0)
            break;
    }
    system("pause");
}

int main()
{
    void Menu();
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    Menu();

}

你需要再定义一个结构体
struct ClassInfo
{
struct student stu[100];
};

只要定义 struct Student* headClass[CLASS_NUM] = {NULL};// 定义班级头节点指针
struct Student* tailClass[CLASS_NUM] = {NULL};
就可以实现多个班级,
如果不会可以帮你写一个demo

#include <stdio.h>
#include <windows.h>//包含了控制台窗口操作相关的函数
#include <stdlib.h>
#define LEN sizeof(struct Student)// 定义结构体类型所占的内存大小
struct Student// 定义结构体类型
{
    char name[10];        
    char number[20];                     
    int C_Language;            
    int Math;                
    int English;    
    struct Student* next;     // 存储下一个学生的地址
};
struct ClassInfo
{
    ClassInfo()
        :head(NULL)
    ,end(NULL){
    };
char name[10];
struct Student* head;// 定义头节点指针
struct Student* end;// 定义尾节点指针
struct ClassInfo* next;
};
int gClassNum = 0;
struct ClassInfo* headClass;// 定义头节点指针
struct ClassInfo* endClass;// 定义尾节点指针
int GetClassNum()
{
    int nClass = 0;
    printf("请输入要操作的班级号码（1~%d）：",gClassNum);
    scanf("%d",&nClass);
    if(nClass<1||nClass>gClassNum)
    {
        
        printf("输入错误，只有%d个班级：",gClassNum);
        nClass=0;
    }
    --nClass;
    return nClass;
}
 void Menu()// 定义菜单函数
 {
     void Menu();// 声明菜单函数
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    void AddClass();
    void ClassRank();
    system("cls"); // 清空控制台窗口内容
    printf("1.学生信息录入\n");
    printf("2.学生单个成绩查询\n");
    printf("3.查询全部学生成绩\n");
    printf("4.修改学生信息\n");
    printf("5.删除学生信息\n");
    printf("6.学生单科成绩录入\n"); 
    printf("7.班级录入\n");
    printf("8.班级排名\n");
    printf("9.退出系统\n");

    int choice;
    printf("请选择要使用的功能：\n");
    loop:
    scanf("%d",&choice);
    switch (choice)
    {
        case 1:
            Add();
            Menu();
        case 2:
            View();
            Menu();
        case 3:
            ViewAll();
            Menu();
        case 4:
            Repair();
            Menu();
        case 5:
            Delete();
            Menu();
        case 6:
            AddOne();
            Menu();
        case 7:
            AddClass();
            Menu();
        case 8:
            ClassRank();
            Menu();
        case 9:
            exit(0);
            default:
                printf("输入有误，请重新选择：");
                break;
    }
} 
 
void Add()
{
    system("cls");
    int count;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    printf("请输入要录入信息的个数：");
    scanf("%d",&count);
    struct Student *s1,*s2,*temp;
    s1=s2=(struct Student*)malloc(LEN);
    if(headClass[nClass].head==NULL)
    {
        headClass[nClass].head = s1;
    }
    else
    {
        headClass[nClass].end->next = s1 ;
    }
    int i = 1;    
    while(count>0)
    {
        printf("请输入第%d位学生信息：\n",i++);
        printf("姓名：\n");
        scanf("%s",&s1->name);
        printf("学号：\n");
        scanf("%s",&s1->number);
        printf("C语言成绩：\n");
        scanf("%d",&s1->C_Language);
        printf("数学成绩:\n");
        scanf("%d",&s1->Math);
        printf("英语成绩:\n");
        scanf("%d",&s1->English);
        count--;
        s2->next=s1;
        s2=s1;
        s1=(struct Student*)malloc(LEN);
        printf("添加成功！\n");
        system("pause");
        system("cls");
    }
    s2->next= NULL;
    headClass[nClass].end = s2;
    printf("全部添加成功！\n");
    system("pause");
}
void View()
{
    system("cls");
    struct Student *VS;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    printf("输入要查询信息的学生学号：\n");
    char num[10];
    int flag=1;
    scanf("%s",&num);
    for(VS=headClass[nClass].head;VS!=NULL;)
    {
        if(strcmp(VS->number,num)==0)
        {
            printf("成功找到！\n");
            printf("姓名：%s\t学号：%s\t\n",VS->number,VS->name);
            printf("C语言：%d\t数学:%d\t英语：%d",VS->C_Language,VS->Math,VS->English);
            flag=0;
            break;
        }
        VS=VS->next;
    }
    if(flag)
    {
        printf("不好意思，未找到！\n");
    }
    system("pause");
}
void ViewAll()
{
    system("cls");
    struct Student *VA;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    if(headClass[nClass].head!=NULL)
    {
        printf("所有学生成绩如下：\n");
        for(VA=headClass[nClass].head;VA!=NULL;)
        {
            printf("姓名：%s\t学号：%s\t\n",VA->name,VA->number);
            printf("C语言：%d\t数学:%d\t英语：%d\n",VA->C_Language,VA->Math,VA->English);
            VA=VA->next; 
        }
        printf("所有不及格科目超过两科的学生名单如下:\n");
        for(VA=headClass[nClass].head;VA!=NULL;)
        {
             int lostNum = 0;
            if(VA->C_Language < 60)
            {
                lostNum++;
            }
            if(VA->Math< 60)
            {
                lostNum++;
            }
            if(VA->English< 60)
            {
                lostNum++;
            }
            if(lostNum > 1)
            {
                printf("姓名：%s\t\n",VA->name);
            }
             VA = VA->next;
        }

    }
    else
    {
        printf("该系统中还未录入信息");
    }
    system("pause");
}
void Repair()
{
    system("cls");
    struct Student *RS;
    char num[10];
    int flag = 1;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    printf("输入要修改成绩学生的学号：\n");
    scanf("%s",num);
    for(RS=headClass[nClass].head;RS!=NULL;)
    {
        if(strcmp(RS->number,num)==0)
        {
            printf("成功找到该学生");
            printf("姓名：%s\t学号：%s\t\n",RS->number,RS->name);
            printf("C语言：%d\t数学:%d\t英语：%d\n",RS->C_Language,RS->Math,RS->English);
            flag = 0;
            printf("姓名：\n");
            scanf("%s",&RS->name);
            printf("学号：\n");
            scanf("%s",&RS->number);
            printf("C语言成绩：\n");
            scanf("%d",&RS->C_Language);
            printf("数学成绩:\n");
            scanf("%d",&RS->Math);
            printf("英语成绩:\n");
            scanf("%d",&RS->English);
            printf("修改成功");
            system("pause");
        }
        RS=RS->next;
    }
    if(flag)
    {
        printf("输入信息有误，未查询到");
        system("pause");
    }
}
void Delete()
{
    system("cls");
    int flag =1;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    while(flag)
    {
        printf("请输入要删除的学生学号：");
        char num[10];
        scanf("%s",&num);
        struct Student * DS,*temp;
        for(DS=headClass[nClass].head;DS!=NULL;)
        {
            if(strcmp(DS->number,num)==0)
            {
                if(DS==headClass[nClass].head)
                {
                    headClass[nClass].head = DS->next;
                    flag = 0;
                    printf("删除成功！\n");
                    system("pause");
                }
                else
                {
                    flag = 0;
                    printf("删除成功！\n");
                    temp->next= DS->next;
                    free(DS);
                    system("pause");
                }
                break;
            }
            temp = DS;
            DS=DS->next;
        }
        if(flag)
        {
            printf("未找到该学生学号！\n");
            system("pause");
        } 
    }
}

 
 
void AddOne()
{
    system("cls");
    struct Student* DA =(struct Student*)malloc(sizeof(struct Student)); //修改1 
    DA->next = NULL; //修改，增加这一行
    int flag = 1;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    while (flag)
    {
        printf("请输入姓名：\n");
        scanf("%s", DA->name);
        printf("请输入学号：\n");
        scanf("%s", DA->number);
        printf("1.录入C语言成绩\n");
        printf("2.录入数学成绩\n");
        printf("3.录入英语成绩\n");
        int select;
        scanf("%d", &select);
        switch (select)
        {
        case 1:
            printf("请输入C语言成绩\n");
            scanf("%d", &DA->C_Language); //修改，增加 &
            break;
        case 2:
            printf("请输入数学成绩\n");
            scanf("%d", &DA->Math);//修改，增加 &
            break;
        case 3:
            printf("请输入英语成绩\n");
            scanf("%d", &DA->English);//修改，增加 &
            break;
        default:
            printf("输入错误，请重新输入\n");
            break;
        }
        printf("录入成功\n");
        flag = 0;
        struct Student* DB, * temp; //修改  DA改成DB
        //DA插入链表
        if (headClass[nClass].head == NULL)
            headClass[nClass].head = DA;
        else
        {
            for (DB = headClass[nClass].head; DB->next != NULL;){
                DB = DB->next;
            }
            DB->next = DA;
        }
        system("pause");
    }
}
void AddClass()
{
    int count=0;
    printf("请输入要录入班级信息的个数：");
    scanf("%d",&count);
    struct ClassInfo *s1,*s2,*temp;
    s1=s2=(struct ClassInfo*)malloc(sizeof(struct ClassInfo));
    s1->head=s1->end=s2->head=s2->end=NULL;
    s1->next=s2->next=NULL;
    if(headClass==NULL)
    {
        headClass = s1;
    }
    else
    {
       endClass->next = s1 ;
    }
    int i = 1;    
    while(count>0)
    {
        printf("请输入第%d班级信息：\n",i++);
        printf("班级：\n");
        scanf("%s",&s1->name);
        count--;
        s2->next=s1;
        s2=s1;
        s1=(struct ClassInfo*)malloc(sizeof(struct ClassInfo));
        ++gClassNum;
        printf("添加成功！\n");
        system("pause");
        system("cls");
    }
    s2->next= NULL;
    endClass = s2;
    printf("全部添加成功！\n");
    system("pause");
}
void Swap(struct Student *VA,struct Student *VB)
{
    struct Student VTmp = *VA;
    struct Student *pTmp = VB->next;
    *VA = *VB;
    *VB = VTmp;
    VB->next = VA->next;
    VA->next = pTmp;
}
void ClassRank()
{
    struct Student *VA=NULL;
    struct Student *VB=NULL;
    int nClass = GetClassNum();
    if (nClass<0)
    {
        return;
    }
    printf("1.C语言成绩排名\n");
    printf("2.数学成绩排名\n");
    printf("3.英语成绩排名\n");
    int select;
    scanf("%d", &select);
    char *pTypeName[]={"C语言","数学","英语"};

    if(headClass[nClass].head!=NULL)
    {
        for(VA=headClass[nClass].head;VA!=NULL;VA=VA->next)
        {
            for(VB=VA->next;VB!=NULL;VB=VB->next)
            {
                switch(select)
                {
                case 1:
                    if( VA->C_Language <VB->C_Language )
                        Swap(VA,VB);
                    break;
                case 2:
                    if( VA->Math <VB->Math )
                        Swap(VA,VB);
                    break;
                case 3:
                    if( VA->English <VB->English )
                        Swap(VA,VB);
                    break;
                }
            }
        }

        printf("%s %s 成绩排名如下：\n",headClass[nClass].name,pTypeName[select-1]);
        for(VA=headClass[nClass].head;VA!=NULL;VA=VA->next)
        {
            printf("姓名：%s\t学号：%s\t\n",VA->name,VA->number);
            printf("C语言：%d\t数学:%d\t英语：%d\n",VA->C_Language,VA->Math,VA->English);
             
        }
    }
    system("pause"); 

}
int main()
{
    void Menu();
    void Add();
    void View();
    void Delete();
    void Repair();
    void ViewAll();
    void AddOne();
    Menu();
    
}

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