C语言问题，有错误，但不知如何解决，请求解答

Question

C语言相关问题
遇到的问题：输入所删掉对应作者后，不能输出。
题目：建立一个链表，每个结点包括：书号、书名、作者、出版社、价格、出版时间。输入一个作者，如果链表中结点所包含的作者等于此作者，则将此结点删去。
代码：

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<string.h>
#include<malloc.h>
struct author
{
    char num[20];
    char name[20];
    char auth[20];
    char public[20];
    float price;
    char time[20];
    struct author* next;
}auth[10];
int main()
{
    struct author* p, * pt, * head;
    p = NULL;
    head = NULL;
    pt = NULL;
    int i, length, flag = 1;
    char iauth[20] = NULL;
    int find = 0;
    while (flag == 1)
    {
        printf("input length of list(<10)\n");
        scanf("%d", &length);
        if (length < 10)
        {
            flag = 0;
        }
    }
    for (i = 0; i < length; i++)
    {
        p = (struct author*)malloc(sizeof(struct author));
        if (i == 0)
            head = pt = p;
        else
            pt->next = p;
        pt = p;
        printf("num.");
        scanf("%s", p->num);
        printf("name:");
        scanf("%s", p->name);
        printf("author:");
        scanf("%s", p->auth);
        printf("public:");
        scanf("%s", p->public);
        printf("price:");
        scanf("%f", &p->price);
        printf("time:");
        scanf("%s", &p->time);
    }
    p->next = NULL;
    p = head;
    printf("\n num. name author public price time\n");
    while (p != NULL)
    {
        printf("%4s%8s%6s%6s%6f%6s\n", p->num, p->name, p->auth, p->public, p->price, p->time);
        p = p->next;
    }
    printf("input author:");
    scanf("%s", iauth);
    pt = head;
    p = pt;
    if (strcmp(pt->auth, iauth))
    {
        p = pt->next;
        head = pt = p;
        find = 1;
    }
    else
        pt = pt->next;
    while (pt != NULL)
    {
        if (strcmp(pt->auth, iauth))
        {
            p->next = pt->next;
            find = 1;
        }
        else
        {
            p = pt;
            pt = pt->next;
        }
    }
    if (!find)
    {
        printf("not found %s", iauth);
    }
    p = head;
    printf("\nnum name author public price time\n");
    while (p != NULL)
    {
        printf("%4s%8s%6s%6s%6f%6s", p->num, p->name, p->auth, p->public, p->price, p->time);
        p = p->next;
    }
    return 0;
}

Answer 1

删除头节点需要特殊处理，因为它没有前一个节点。
使用strcmp函数时，当两个字符串相等时，该函数返回0。您的代码中对stremp的使用是错误的。
初始化字符数组时不应该使用NULL。如果您需要初始化为空字符串，应该使用""。
scanf（"%s"，&p->time）中的&是不需要的，因为数组名已经是一个地址。
以下是修改后的代码

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

struct author {
    char num[20];
    char name[20];
    char auth[20];
    char public[20];
    float price;
    char time[20];
    struct author* next;
};

int main() {
    struct author *p, *pt, *head, *prev;
    head = NULL;
    int length, flag = 1;
    char iauth[20] = ""; // 初始化为空字符串
    int find = 0;

    // 输入链表长度
    while (flag == 1) {
        printf("input length of list(<10)\n");
        scanf("%d", &length);
        if (length < 10) {
            flag = 0;
        }
    }

    // 创建链表
    for (int i = 0; i < length; i++) {
        p = (struct author*)malloc(sizeof(struct author));
        if (i == 0)
            head = p;
        else
            pt->next = p;
        pt = p;

        printf("num: ");
        scanf("%s", p->num);
        printf("name: ");
        scanf("%s", p->name);
        printf("author: ");
        scanf("%s", p->auth);
        printf("public: ");
        scanf("%s", p->public);
        printf("price: ");
        scanf("%f", &p->price);
        printf("time: ");
        scanf("%s", p->time);
        p->next = NULL;
    }

    // 显示链表
    printf("\n num. name author public price time\n");
    for (p = head; p != NULL; p = p->next) {
        printf("%4s %8s %6s %6s %6.2f %6s\n", p->num, p->name, p->auth, p->public, p->price, p->time);
    }

    // 删除特定作者的节点
    printf("input author:");
    scanf("%s", iauth);

    pt = head;
    prev = NULL;
    while (pt != NULL) {
        if (strcmp(pt->auth, iauth) == 0) { // 当找到匹配的作者时
            if (pt == head) { // 特殊处理头节点
                head = pt->next;
            } else {
                prev->next = pt->next;
            }
            free(pt);
            find = 1;
            if (prev != NULL) { // 如果不是删除的头节点
                pt = prev->next;
            } else { // 如果删除的是头节点
                pt = head;
            }
        } else {
            prev = pt;
            pt = pt->next;
        }
    }

    if (!find) {
        printf("not found %s\n", iauth);
    }

    // 显示删除后的链表
    printf("\nnum name author public price time\n");
    for (p = head; p != NULL; p = p->next) {
        printf("%4s %8s %6s %6s %6.2f %6s\n", p->num, p->name, p->auth, p->public, p->price, p->time);
    }

    // 清理链表
    p = head;
    while (p != NULL) {
        struct author* temp = p;
        p = p->next;
        free(temp);
    }

    return 0;
}

这个程序还包含了清理链表的代码，以释放分配的内存......