用C语言链表实现图书管理

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct ListNode {
    int val;//编号
    char title[50];//书名
    float price;//价格
    struct ListNode* next;
};

// 在尾部插入节点
struct ListNode* insertAtTail(struct ListNode* head, int val,char mytitle[50],float price) {
    struct ListNode* new_node = (struct ListNode*)malloc(sizeof(struct ListNode));
    new_node->val = val;
    strcpy(new_node->title,mytitle);
    new_node->price=price;
    new_node->next = NULL;
    if (head == NULL) {
        return new_node;
    }
    struct ListNode* p = head;
    while (p->next != NULL) {
        p = p->next;
    }

    p->next = new_node;
    return head;
}
void listAll(struct ListNode* head){
    printf("编号\t书名\t价格\n");
    struct ListNode* p=head;
    while(p!=NULL){
        printf("%d\t%s\t%f", p->val, p->title, p->price);
        printf("\n");
        p=p->next;
    }
}
// 删除指定值的节点
struct ListNode* deleteNode(struct ListNode* head, int val) {
    struct ListNode* p = head;
    struct ListNode* prev = NULL;
 
    while (p != NULL && p->val != val) {
        prev = p;
        p = p->next;
    }
 
    if (p == NULL) {
        return head;
    }
 
    if (prev == NULL) {
        head = head->next;
    } else {
        prev->next = p->next;
    }
 
    free(p);
 
    return head;
}
// 修改指定值的节点的值
struct ListNode* modifyNode(struct ListNode* head, int old_val,char newTitle[50],float newPrice) {
    struct ListNode* p = head;
 
    while (p != NULL && p->val != old_val) {
        p = p->next;
    }
    if (p == NULL) {
        return head;
    }
    strcpy(p->title  ,newTitle);
    p->price = newPrice;
 
    return head;
}
// 查找指定值的节点的位置
int getIndexByVal(struct ListNode* head, int val) {
    struct ListNode* p = head;
    int i = 0;
 
    while (p != NULL && p->val != val) {
        p = p->next;
        i++;
    }
    if (p == NULL) {
        return -1;
    }
 
    return i;
}
int main(){
   
  
    struct ListNode* p=NULL;
   
   for (int i = 0; i < 100; i++)
    {
        printf("%s", "1.插入图书\n");
        printf("%s", "2.删除图书\n");
        printf("%s", "3.图书列表\n");
        printf("%s", "4.修改图书\n");
        printf("%s", "请输入1或2或3或4：\n");
        int select;
        scanf("%d", &select);
       
        if (select == 1)
        {
            int myVal;
            printf( "请输入编号：\n");
            scanf("%d", &myVal);
            printf( "请输入书名：\n");
            char myTitle[50];
            scanf("%s", myTitle);
            printf( "请输入价格：\n");
            float myPrice;
            scanf("%f",&myPrice);
            if(p==NULL){
                p=insertAtTail(NULL,myVal,myTitle,myPrice);

            }else{
                p=insertAtTail(p,myVal,myTitle,myPrice);
            }
        }else if(select==3){
            listAll(p);
        }else if(select==2){
            int deleteVal;
            printf("请输入要删除的图书的编号：\n");
            scanf("%d",&deleteVal);
            p=deleteNode(p,deleteVal);
        }else if(select==4){
            int modifyVal;
            printf("请输入要修改的图书的编号：\n");
            scanf("%d",&modifyVal);
            if(getIndexByVal(p,modifyVal)==-1){
                printf("图书不存在");
                continue;
            }
            printf( "请输入书名：\n");
            char modifyTitle[50];
            scanf("%s", modifyTitle);
            printf( "请输入价格：\n");
            float modifyPrice;
            scanf("%f",&modifyPrice);
            p=modifyNode(p,modifyVal,modifyTitle,modifyPrice);
        }


    }
   
    
    return 0;
}
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要改成班级管理，ListNode中val不变，其它属性变成学生姓名、成绩等等。
注意：c语言的编译不要用visual studio，因为它连scanf都会报错，会要求您使用scanf_s。建议用记事本或visual studio code编写,然后在命令行窗口输入gcc命令来编译。