链表删除节点问题

[biu__biu_biu]

delete函数不能删除第一个节点（fuck_1），出现段错误；请教各位大佬，错误在哪儿。

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

struct person
{
    char *labe;
    struct person *pre;
    struct person *next;
};

struct jack
{
    struct person p;
    char name[10];
    char food[10];
};

struct fuck
{
    struct person p;
    char name[10];
    char food[10];
};

void print_jack(struct person *curr)
{
    struct jack *t = (struct jack *)curr;

    printf("%s eat %s\n",t->name,t->food);
}

void print_fuck(struct person *curr)
{
    struct fuck *t = (struct fuck *)curr;

    printf("%s eat %s\n",t->name,t->food);
}

void head_list(struct person **head, struct person *n)
{
    n->pre = NULL;
    n->next = *head;
    if(NULL != *head)
    {
        (*head)->pre = n;
    }
    *head = n;
}

void travers(struct person *head, void (*fp)(struct person *))
{
    fp(head);
}


void show(struct person *head)
{
    if(NULL == head)
    {
        return;
    }
    while(head)
    {
        if(0 == strcmp(head->labe, "jack"))
        {
            travers(head,print_jack);
        }
        else
        {
            travers(head,print_fuck);
        }
        head = head->next;
    }
}


void delete(struct person *head,void *key)
{
    int ret = 0;
    struct person *past = head;
    struct person *curr = past;

    while(curr)
    {
        if(0 == strcmp(curr->labe,"jack"))
        {
            if(0 == strcmp(((struct jack *)curr)->name, (char *)key))
            {
                past->next = curr->next;
                free(curr);
                curr = NULL;
                ret += 1;
            }
        }
        else
            if(0 == strcmp(curr->labe,"fuck"))
            {
                if(0 == strcmp(((struct fuck *)curr)->name, (char *)key))
                {
                    past->next = curr->next;
                    free(curr);
                    curr = NULL;
                    ret += 1;
                }
            }
        if(0 == ret)
        {
            past = curr;
            curr = curr->next;
        }
    }
}

int main()
{
    int i = 5;
    char jack[5][10] = {"jack_1","jack_2","jack_3","jack_4","jack_5"};
    char jfd[10] = {"orange"};
    char fuck[5][10] = {"fuck_1","fuck_2","fuck_3","fuck_4","fuck_5"};
    char ffd[10] = {"apple"};
    struct person *head = NULL;

    while(i--)
    {
        struct jack *j = (struct jack *)malloc(sizeof(struct jack));

        strcpy(j->name,jack[i]);
        strcpy(j->food,jfd);
        j->p.labe = "jack";
        head_list(&head,&j->p);

        struct fuck *f = (struct fuck *)malloc(sizeof(struct fuck));

        strcpy(f->name,fuck[i]);
        strcpy(f->food,ffd);
        f->p.labe = "fuck";
        head_list(&head,&f->p);
    }

    printf("=============\n");
    delete(head,"fuck_1");
    show(head);
    return 0;
}

[自信男孩]

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

struct person
{
    char *labe;
    struct person *pre;
    struct person *next;
};

struct jack
{
    struct person p;
    char name[10];
    char food[10];
};

struct fuck
{
    struct person p;
    char name[10];
    char food[10];
};

void print_jack(struct person *curr)
{
    struct jack *t = (struct jack *)curr;

    printf("%s eat %s\n",t->name,t->food);
}

void print_fuck(struct person *curr)
{
    struct fuck *t = (struct fuck *)curr;

    printf("%s eat %s\n",t->name,t->food);
}

void head_list(struct person **head, struct person *n)
{
    n->pre = NULL;
    n->next = *head;
    if(NULL != *head)
    {
        (*head)->pre = n;
    }
    *head = n;
}

void travers(struct person *head, void (*fp)(struct person *))
{
    fp(head);
}


void show(struct person *head)
{
    if(NULL == head)
    {
        return;
    }
    while(head)
    {
        if(0 == strcmp(head->labe, "jack"))
        {
            travers(head,print_jack);
        }
        else
        {
            travers(head,print_fuck);
        }
        head = head->next;
    }
}


void delete(struct person **head,void *key)
{
    int ret = 0;
    struct person *past = *head;
    struct person *curr = past;

    while(curr)
    {
        if(0 == strcmp(curr->labe,"jack"))
        {
            if(0 == strcmp(((struct jack *)curr)->name, (char *)key))
            {
                if (curr == *head) {
                    (*head)->next->pre = (*head)->pre;
                    (*head) = (*head)->next;
                } else {
                    curr->next->pre = past;
                    past->next = curr->next;
                }
                free(curr);
                curr = NULL;
                ret += 1;
            }
        }
        else if(0 == strcmp(curr->labe,"fuck")) {
            if(0 == strcmp(((struct fuck *)curr)->name, (char *)key))
            {
                if (curr == *head) {
                    (*head)->next->pre = (*head)->pre;
                    (*head) = (*head)->next;
                } else {
                    curr->next->pre = past;
                    past->next = curr->next;
                }
                //past->next = curr->next;
                //curr->next->pre = past;
                free(curr);
                curr = NULL;
                ret += 1;
            }
        }
        if(0 == ret)
        {
            past = curr;
            curr = curr->next;
        }
        printf("helloworld!\n");
    }
}


void del_person(struct person **head,void *key)
{
    int ret = 0;
    struct person *past = *head;
    struct person *curr = past;

    while(curr)
    {

        if( (0 == strcmp(curr->labe,"jack") && 0 == strcmp(((struct jack *)curr)->name, (char *)key))
               || (0 == strcmp(curr->labe,"fuck") && 0 == strcmp(((struct fuck *)curr)->name, (char *)key))) {
                if (curr == *head) {
                    (*head)->next->pre = (*head)->pre;
                    (*head) = (*head)->next;
                } else {
                    curr->next->pre = past;
                    past->next = curr->next;
                }
                free(curr);
                curr = NULL;
                ret += 1;
        }
        if(0 == ret)
        {
            past = curr;
            curr = curr->next;
        }
    }
}

int main(void)
{
    int i = 5;
    char jack[5][10] = {"jack_1","jack_2","jack_3","jack_4","jack_5"};
    char jfd[10] = {"orange"};
    char fuck[5][10] = {"fuck_1","fuck_2","fuck_3","fuck_4","fuck_5"};
    char ffd[10] = {"apple"};
    struct person *head = NULL;

    while(i--)
    {
        struct jack *jk = (struct jack *)malloc(sizeof(struct jack));

        strcpy(jk->name,jack[i]);
        strcpy(jk->food,jfd);
        jk->p.labe = "jack";
        head_list(&head,&jk->p);

        struct fuck *fk = (struct fuck *)malloc(sizeof(struct fuck));

        strcpy(fk->name,fuck[i]);
        strcpy(fk->food, ffd);
        fk->p.labe = "fuck";
        head_list(&head, &fk->p);
    }

    printf("Show list: \n");
    show(head);
    printf("=============\n");
    delete(&head, "fuck_1");
    //del_person(&head, "fuck_1");
    printf("Show list(After delete fuck_1): \n");
    show(head);
    return 0;
}

参考一下吧。delete函数逻辑是有问题的，上面是已经改过的。 另外，考虑你的delete函数代码逻辑有冗余，所以用del_person函数重写了你的这个功能。建议多测试删除的情况，这是删除头，试着删除中间节点和尾节点，都试试看看有没有问题。 看你的这个链表数据结构设计比较独特，看着像内核的链表结构设计。

[biu__biu_biu]

感谢，还要考虑最后一个的情况，加上

 while(curr)
    {
        if(0 == strcmp(curr->labe,"jack"))
        {
            if(0 == strcmp(((struct jack *)curr)->name, (char *)key))
            {
                if(curr == *head)
                {
                    (*head)->next->pre = (*head)->pre;
                    *head = (*head)->next;
                }
                if(curr->next == NULL)  //考虑最后一个
                {
                    curr->pre->next = NULL;
                }
                else
                {
                    curr->next->pre = past;
                    past->next = curr->next;
                }
                free(curr);
                curr = NULL;
                ret += 1;
            }
        }

[自信男孩]

引用 2 楼 biu__biu_biu 的回复:

感谢，还要考虑最后一个的情况，加上

 while(curr)
    {
        if(0 == strcmp(curr->labe,"jack"))
        {
            if(0 == strcmp(((struct jack *)curr)->name, (char *)key))
            {
                if(curr == *head)
                {
                    (*head)->next->pre = (*head)->pre;
                    *head = (*head)->next;
                }
                if(curr->next == NULL)  //考虑最后一个
                {
                    curr->pre->next = NULL;
                }
                else
                {
                    curr->next->pre = past;
                    past->next = curr->next;
                }
                free(curr);
                curr = NULL;
                ret += 1;
            }
        }

不用考虑，因为你的是双向循环链表。所以没有指向NULL的节点，最后一个节点的next指向head