无头单向非循环链表（C语言实现）（包括链表的增删改查打印和）

无头单向非循环链表

1、链表的概念

链表是一种物理存储结构上非连续的、非顺序的存储结构，数据元素的逻辑顺序是通过链表中的指针链接次序实现

2、链表的结构

1、单向、双向
2、带头、不带头
3、循环、非循环
共有八种结构

常见链表分别是无头单向非循环链表和带头双向循环链表
1、无头单向非循环链表
常作为其他结构的底层结构，如哈希桶、图的邻接表
2、带头双向循环链表
结构最复杂，实际使用的链表数据结构。

无头单向非循环链表

//带头结点的单向非循环链表
typedef int SLTDataType;

typedef struct SListNode
{
	SLTDataType data;
	struct SListNode *next;
}SListNode;

typedef struct SList
{
	SListNode *head;
}SList;

SList.h

#ifndef _SLIST_H_
#define _SLIST_H_

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
//带头结点的单向非循环链表
typedef int SLTDataType;

typedef struct SListNode
{
	SLTDataType data;
	struct SListNode *next;
}SListNode;

typedef struct SList
{
	SListNode *head;
}SList;

//初始化
void SListInit(SList *plist);
//销毁
void SListDestory(SList *plist);
//为x申请结点
SListNode* BuySListNode(SLTDataType x);
//头插
void SListPushFront(SList *plist, SLTDataType x);
//头删
void SListPopFront(SList *plist);
//尾插
void SListPushBack(SList *plist, SLTDataType x);
//尾删
void SListPopBack(SList *plist);
//在pos位置之后插入
void SListInsertAfter(SList *plist, SListNode *pos, SLTDataType x);
//在pos位置之前插入
void SListInsertBefore(SList *plist, SListNode *pos, SLTDataType x);
//删除pos结点
void SListErasePos(SListNode *pos);
//查找元素x
SListNode* SListFind(SList *plist, SLTDataType x);
//删除元素x
void SListEraseX(SList *plist, SLTDataType x);
//修改值
void SListModify(SListNode *pos, SLTDataType x);
//打印
void SListPrint(SList *plist);

#endif //_SLITS_H_

SList.c

#include "SList.h"

//初始化
void SListInit(SList *plist)
{
	assert(plist);
	plist->head = NULL;
}

//销毁
void SListDestory(SList *plist)
{
	assert(plist);
	SListNode *cur = plist->head;
	SListNode *next;
	while (cur)
	{
		next = cur->next;
		free(cur);
		cur = next;
	}
	plist->head = NULL;
}

//为x申请结点
SListNode* BuySListNode(SLTDataType x)
{
	SListNode *node = (SListNode *)malloc(sizeof(SListNode));
	assert(node);
	node->data = x;
	node->next = NULL;
	return node;
}

//头插
void SListPushFront(SList *plist, SLTDataType x)
{
	assert(plist);
	SListNode *node = BuySListNode(x);
	assert(node);
	node->next = plist->head;
	plist->head = node;
}

//头删
void SListPopFront(SList *plist)
{
	assert(plist);
	assert(plist->head);
	SListNode *cur = plist->head;
	plist->head = plist->head->next;
	free(cur);
	cur = NULL;
}

//尾插
void SListPushBack(SList *plist, SLTDataType x)
{
	assert(plist);
	if (plist->head == NULL)
	{
		SListPushFront(plist, x);
		return;
	}
	SListNode *cur;
	for (cur = plist->head; cur->next != NULL; cur = cur->next)
	{

	}
	SListNode *node = BuySListNode(x);
	cur->next = node;
}

//尾删
void SListPopBack(SList *plist)
{
	assert(plist);
	assert(plist->head);
	if (plist->head->next == NULL)
	{
		SListPopFront(plist);
		return;
	}
	SListNode *cur = plist->head;
	while (cur->next->next != NULL)
	{
		cur = cur->next;
	}
	free(cur->next);
	cur->next = NULL;
}

//在pos位置之后插入
void SListInsertAfter(SList *plist, SListNode *pos, SLTDataType x)
{
	assert(plist);
	SListNode *node = BuySListNode(x);
	node->next = pos->next;
	pos->next = node;
}

//在pos位置之前插入
void SListInsertBefore(SList *plist, SListNode *pos, SLTDataType x)
{
	assert(plist);
	SListNode *cur = plist->head;
	while (cur->next != pos)
	{
		cur = cur->next;
	}
	SListNode *node = BuySListNode(x);
	node->next = cur->next;
	cur->next = node;
}

//删除pos结点
void SListErasePos(SListNode *pos)
{
	SListNode *cur = pos->next;
	pos->next = cur->next;
	free(cur);
	cur = NULL;
}

//查找元素x
SListNode* SListFind(SList *plist, SLTDataType x)
{
	assert(plist);
	for (SListNode *cur = plist->head; cur != NULL; cur = cur->next)
	{
		if (cur->data == x)
		{
			return cur;
		}
	}
	return NULL;
}

//删除元素x
void SListEraseX(SList *plist, SLTDataType x)
{
	assert(plist);
	SListNode *pos = SListFind(plist, x);
	SListErasePos(pos);
}

//修改值
void SListModify(SListNode *pos, SLTDataType x)
{
	pos->data = x;
}

//打印
void SListPrint(SList *plist)
{
	assert(plist);
	for (SListNode *cur = plist->head; cur != NULL; cur = cur->next)
	{
		printf("%d --> ", cur->data);
	}
	printf("NULL\n");
}

main.c

#include "SList.h"

int main()
{
	SList plist;
	SListInit(&plist);
	SListPrint(&plist);
	
	SListPushBack(&plist, 1);
	SListPushBack(&plist, 2);
	SListPushBack(&plist, 3);
	SListPushBack(&plist, 4);
	SListPushBack(&plist, 5);
	SListPushBack(&plist, 6);
	SListPushBack(&plist, 7);
	SListPushBack(&plist, 8);
	SListPushBack(&plist, 9);
	SListPushBack(&plist, 10);
	SListPrint(&plist);

	SListPushFront(&plist, 0);
	SListPrint(&plist);

	SListPopFront(&plist);
	SListPrint(&plist);

	SListPopBack(&plist);
	SListPrint(&plist);

	SListNode *pos = SListFind(&plist, 5);

	SListInsertBefore(&plist, pos, 6);
	SListPrint(&plist);
	SListInsertAfter(&plist, pos, 4);
	SListPrint(&plist);
	SListErasePos(pos);
	SListPrint(&plist);
	SListEraseX(&plist, 3);
	SListPrint(&plist);
	SListDestory(&plist);
	system("pause");
	return  0;
}