数据结构与算法：单向链表实现与封装(有头)

概述

单向链表分为单向有头链表和单线无头链表，本文针对单向有头链表使用C语言来实现并进行封装。

实现

list_head.h文件

#ifndef _LIST_H_
#define _LIST_H_

typedef int datatype;


#define SUCC
#define MALLOC_FAIL		1
#define NOHEADNODE		2
#define	INDEXFAIL		3
#define LIST_EMPTY		4
#define LIST_NOEMPTY	5
#define FAIL			10

typedef struct List_Node 
{
	datatype data;
	struct List_Node* pNext;
}list;

list*list_create();

int	 list_insert_at(list* pHead, int i, datatype* pData);
int	 list_order_insert(list* pHead, datatype* pData);

int  list_delete_at(list* pHead, int index);
int  list_delete(list* pHead, datatype* pData);

int	 list_isempty(list* pHead);
void list_display(list* pHead);
void list_destory(list* pHead);

#endif // !_LIST_H_

list_head.c文件

/********************************************************
Copyright (C), 2016-2017,
FileName: 	list
Author: 	woniu201
Email: 		wangpengfei.201@163.com
Created: 	2018/01/28
Description:单向有头链表使用
********************************************************/

#include <stdio.h>
#include "list_head.h"


/************************************
@ Brief:		创建链表头
@ Author:		woniu201 
@ Created: 		2018/01/28
@ Return:		    
************************************/
list*	list_create()
{
	list* pNode = (list *)malloc(sizeof(list));
	memset(pNode, 0, sizeof(list));
	if (pNode == NULL)
	{
		return MALLOC_FAIL;
	}
	pNode->pNext = NULL;

	return pNode;
}

/************************************
@ Brief:		按位置插入节点
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
int	list_insert_at(list* pHead, int i, datatype* pData)
{
	int j = 0;
	if (pHead == NULL)
	{
		return NOHEADNODE;
	}
	list* pNode = pHead;
	
	if (i<0)
	{
		return INDEXFAIL;
	}
	while (j< i && pNode !=NULL)
	{
		pNode = pNode->pNext;
		j++;
	}
	
	if (pNode == NULL)
	{
		return INDEXFAIL;
	}
	else
	{
		list* newNode = (list*)malloc(sizeof(list));
		if (newNode ==NULL)
		{
			return MALLOC_FAIL;
		}
		memset(newNode, 0, sizeof(list));
		newNode->data = *pData;

		pNode->pNext = newNode;
	}

	return SUCC;
}

/************************************
@ Brief:		按顺序插入节点
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
int	list_order_insert(list* pHead, datatype* pData)
{
	if (pHead == NULL)
	{
		return NOHEADNODE;
	}
	list*  pNewNode = (list*)malloc(sizeof(list));
	if (pNewNode  == NULL)
	{
		return MALLOC_FAIL;
	}
	memset(pNewNode, 0, sizeof(list));
	pNewNode->data = *pData;


	list* pNode = pHead;
	if (pNode->pNext == NULL)
	{
		pNode->pNext = pNewNode;
		return SUCC;
	}
	while (pNode->pNext != NULL && pNode->pNext->data < *pData)
	{
		pNode = pNode->pNext;
	}
    if (pNode->pNext)
    {
		pNewNode->pNext = pNode->pNext;
		pNode->pNext = pNewNode;
    }
	else
	{
		pNode->pNext = pNewNode;
	}
	return SUCC;
}

/************************************
@ Brief:		按位置删除节点
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
int	list_delete_at(list* pHead, int index)
{
	int j = 0;
	if (pHead == NULL)
	{
		return NOHEADNODE;
	}
	if (index < 0)
	{
		return INDEXFAIL;
	}
	list* pCur = pHead;
	list* pNode = pHead;

	
	while (pCur->pNext)
	{
		pNode = pCur;
		pCur = pCur->pNext;
		if (index == j)
		{
			break;
		}
		j++;
	}
	if (j< index)
	{
		printf("不存在该节点
");
		return INDEXFAIL;
	}
	else
	{
		if (pCur->pNext == NULL)
		{
			pNode->pNext = NULL;
		}
		else
		{
			pNode->pNext = pCur->pNext;
		}
		free(pCur);
		pCur = NULL;
	}
	return SUCC;
}

/************************************
@ Brief:		按值删除节点
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
int  list_delete(list* pHead, datatype* pData)
{
	if (pHead == NULL)
	{
		return NOHEADNODE;
	}
	list* pCur = pHead;
	list* pNode = pHead;

	int bFind = 0;
	while (pCur->pNext)
	{
		pNode = pCur;
		pCur = pCur->pNext;
		if (pCur->data == *pData)
		{
			bFind = 1;
			break;
		}
	}
	if (!bFind)
	{
		printf("不存在该节点
");
		return INDEXFAIL;
	}
	else
	{
		if (pCur->pNext == NULL)
		{
			pNode->pNext = NULL;
		}
		else
		{
			pNode->pNext = pCur->pNext;
		}
		free(pCur);
		pCur = NULL;
	}
	return SUCC;
}

/************************************
@ Brief:		判断链表是否为空
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
int	list_isempty(list* pHead)
{
	if (pHead->pNext == NULL)
	{
		return LIST_EMPTY;
	}
	else
	{
		return LIST_NOEMPTY;
	}
}

/************************************
@ Brief:		遍历打印链表
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
void	list_display(list* pHead)
{
	if (list_isempty(pHead) == LIST_EMPTY)
	{
		printf("链表为空
");
		return FAIL;
	}
	list* pNode = pHead->pNext;
	while (pNode)
	{
		printf("%d
", pNode->data);
		pNode = pNode->pNext;
	}
}

/************************************
@ Brief:		释放链表内存
@ Author:		woniu201
@ Created: 		2018/01/28
@ Return:
************************************/
void    list_destory(list* pHead)
{
	list* pCur = pHead;
	list* pNext = pHead->pNext;

	while (pNext)
	{
		pNext = pNext->pNext;
		free(pCur);
		pCur = NULL;
		pCur = pNext;
	}
}

main.c 测试

#include <stdio.h>
#include "list_head.h"

int main()
{
	list* pHead = list_create();

	int data1 = 1;
	int data2 = 3;
	int data3 = 2;

// 	int ret = list_insert_at(pHead,0, &data1);
// 	ret = list_insert_at(pHead, 1, &data2);
// 	if (ret == INDEXFAIL)
// 	{
// 		printf("添加索引位置错误
");
// 	}

	list_order_insert(pHead, &data2);
	list_order_insert(pHead, &data1);
	list_order_insert(pHead, &data3);

	list_delete_at(pHead,  3);
	int deleteData = 1;
	list_delete(pHead, &deleteData);
	list_display(pHead);
	list_destory(pHead);
	return 1;
}