c - 所有数据类型的单向链表，实现C语言的插入、删除、查找元素

Question

所以我设法想出了一种仅适用于整数的语法。我如何编写所有数据类型的语法，最好使用 typedef和void*现在也想知道如何使用 void push_back命令。？

它创建一个链接列表，添加节点，删除节点并查找列表中的任何节点。第一个节点始终可以通过全局“头”指针进行访问。当第一个节点被删除时，该指针会被调整。类似地，有一个“curr”指针包含列表中的最后一个节点。当删除最后一个节点时，也会对此进行调整。每当向链表添加节点时，总是检查链表是否为空，然后将其添加为第一个节点。

有没有其他方法可以在不使用 #include<stdbool.h> 的情况下添加、删除和查找链表中的节点？

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

struct test_struct
{
    int val;
    struct test_struct *next;
};

struct test_struct *head = NULL;
struct test_struct *curr = NULL;

struct test_struct* create_list(int val)
{
    printf("\n creating list with headnode as [%d]\n",val);
    struct test_struct *ptr = (struct test_struct*)malloc(sizeof(struct test_struct));
    if(NULL == ptr)
    {
        printf("\n Node creation failed \n");
        return NULL;
    }
    ptr->val = val;
    ptr->next = NULL;

    head = curr = ptr;
    return ptr;
}

struct test_struct* add_to_list(int val, bool add_to_end)
{
    if(NULL == head)
    {
        return (create_list(val));
    }

    if(add_to_end)
        printf("\n Adding node to end of list with value [%d]\n",val);
    else
        printf("\n Adding node to beginning of list with value [%d]\n",val);

    struct test_struct *ptr = (struct test_struct*)malloc(sizeof(struct test_struct));
    if(NULL == ptr)
    {
        printf("\n Node creation failed \n");
        return NULL;
    }
    ptr->val = val;
    ptr->next = NULL;

    if(add_to_end)
    {
        curr->next = ptr;
        curr = ptr;
    }
    else
    {
        ptr->next = head;
        head = ptr;
    }
    return ptr;
}

struct test_struct* search_in_list(int val, struct test_struct **prev)
{
    struct test_struct *ptr = head;
    struct test_struct *tmp = NULL;
    bool found = false;

    printf("\n Searching the list for value [%d] \n",val);

    while(ptr != NULL)
    {
        if(ptr->val == val)
        {
            found = true;
            break;
        }
        else
        {
            tmp = ptr;
            ptr = ptr->next;
        }
    }

    if(true == found)
    {
        if(prev)
            *prev = tmp;
        return ptr;
    }
    else
    {
        return NULL;
    }
}

int delete_from_list(int val)
{
    struct test_struct *prev = NULL;
    struct test_struct *del = NULL;

    printf("\n Deleting value [%d] from list\n",val);

    del = search_in_list(val,&prev);
    if(del == NULL)
    {
        return -1;
    }
    else
    {
        if(prev != NULL)
            prev->next = del->next;

        if(del == curr)
        {
            curr = prev;
        }
        else if(del == head)
        {
            head = del->next;
        }
    }

    free(del);
    del = NULL;

    return 0;
}

void print_list(void)
{
    struct test_struct *ptr = head;

    printf("\n -------Printing list Start------- \n");
    while(ptr != NULL)
    {
        printf("\n [%d] \n",ptr->val);
        ptr = ptr->next;
    }
    printf("\n -------Printing list End------- \n");

    return;
}

int main(void)
{
    int i = 0, ret = 0;
    struct test_struct *ptr = NULL;

    print_list();

    for(i = 5; i<10; i++)
        add_to_list(i,true);

    print_list();

    for(i = 4; i>0; i--)
        add_to_list(i,false);

    print_list();

    for(i = 1; i<10; i += 4)
    {
        ptr = search_in_list(i, NULL);
        if(NULL == ptr)
        {
            printf("\n Search [val = %d] failed, no such element found\n",i);
        }
        else
        {
            printf("\n Search passed [val = %d]\n",ptr->val);
        }

        print_list();

        ret = delete_from_list(i);
        if(ret != 0)
        {
            printf("\n delete [val = %d] failed, no such element found\n",i);
        }
        else
        {
            printf("\n delete [val = %d]  passed \n",i);
        }

        print_list();
    }

    return 0;
}

Answer 1

Is there anyother way to add,delete and find nodes in a linked list without using #include<stdbool.h> ?

是的，不要在代码中使用任何 bool 类型。