数据结构基本算法：单向链表

链表操作

最新推荐文章于 2022-05-15 10:45:28 发布

原创最新推荐文章于 2022-05-15 10:45:28 发布 · 915 阅读

1 ·

CC 4.0 BY-SA版权

文章标签：

#数据结构 #算法 #struct #null #list #c

技术专栏专栏收录该内容

15 篇文章

订阅专栏

本文介绍了一个简单的链表实现，包括添加、删除元素等基本操作，并提供了一段测试代码以验证链表的功能。

#include<stdio.h>
#include<malloc.h>

struct LinkedList
{
    char data;
    struct LinkedList *next;
};

struct LinkedList *LinkedList;

//Gets the count the elements in the list.
int GetLinkedListLength()
{
    int length=0;
    struct LinkedList *p = LinkedList;
    while(p!=NULL)
    {
        p=p->next;/*Moves the pointer to the next element.*/
        length++;
    }
    return length;
}

//Gets the element by the given index.
struct LinkedList *GetLinkedListNodeByIndex(int index)
{
    int currentIndex;
    int length = GetLinkedListLength();
    struct LinkedList *node = NULL;

    if((index>=0) && (index<length))
    {
        node = LinkedList;
        for(currentIndex=1;currentIndex<=index;currentIndex++)
        {
                node =     node->next;
        }
    }
    return node;
}

//Shows all elments in the list.
void ShowData()
{
        struct LinkedList *p = LinkedList;
        while(p!=NULL)
        {
            printf("%c/t",p->data);
            p = p->next;
        }
        printf("/n");
}

//Add an element into the list.
void AddElement(char data, int index)
{
    int length = GetLinkedListLength();
    struct LinkedList *temNode;
    struct LinkedList *p;

    if((index<0) || (index>length))
    {
        printf("Index is ilegal./n");
        return;
    }

    //Initializes the tem node.
    temNode = (struct LinkedList *)malloc(sizeof(struct LinkedList));
    temNode->data = data;
    temNode->next = NULL;

    if(length == 0)/*The linkedList is empty now.*/
    {
        LinkedList = temNode;
    }
    else
    {
        p = GetLinkedListNodeByIndex(index-1);

        if(p == NULL)
        {
            temNode->next = LinkedList;
            LinkedList = temNode;
        }
        else
        {
            temNode->next = p->next;
            p->next = temNode;
        }
    }

}

//Deletes a element by the given index.
void DeleteElement(int index)
{
        int length = GetLinkedListLength();
        struct LinkedList *father;
        struct LinkedList *nodeToDelete;

        if(length == 0)
        {
            printf("The list is empty now, can not delete./n");
            return;
        }

        if((index<0) || (index>length - 1))
        {
            printf("Index is ilegal./n");
            return;
        }

        father = GetLinkedListNodeByIndex(index - 1);

        if(father == NULL)
        {
            nodeToDelete = LinkedList;
            LinkedList = LinkedList->next;
        }
        else
        {
            nodeToDelete = father->next;
            father->next = nodeToDelete->next;
        }
        free(nodeToDelete);
}

//Mokes some elements.
void InitializeLinkedList()
{
        AddElement('A',0);
        AddElement('B',1);
        AddElement('C',1);
        AddElement('D',2);
        AddElement('E',0);
        AddElement('F',0);
}

//Tests the methods.
void TestLinkedList()
{
    InitializeLinkedList();
    ShowData();
    DeleteElement(0);
    ShowData();
}