C语言实现单向链表

结合我所写代码，pplist是一个二级指针，**pplist是首元素内的内容，*pplist可以表示整个链表的地址，类似于数组首元素地址与数组地址,这里用一个pplist二级指针，可以将链表地址，链表首元素地址.链表的结构大体如下图所示：



下面就是链表的各个函数代码了：

一个头文件（各个函数的声明），两个源文件（一个函数功能的实现，一个是测试函数功能的正确性）

头文件代码：

#define _CRT_SECURE_NO_WARNINGS 1

#ifndef __LIST_H__
#define __LIST_H__

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

typedef int Datatype;

typedef struct Node
{
Datatype d;//结构体内所存数据
struct Node* next;//后半部分所存下个数据地址
}Node, *pNode,*pList;

void InitList(pList *pplist);//初始化链表
void PushBack(pList *pplist,Datatype x);//尾插
void PopBack(pList *pplist);//尾删
void PushFront(pList *pplist,Datatype x);//头插
void PopFront(pList *pplist);头删
void Print(const pList *ppplist);//打印链表
void DistroyList(pList *pplist);//销毁链表
pNode Find(pList *pplist, Datatype x);查找指定数据元素
void Remove(pList *pplist, Datatype x);//删除指定元素
void RemoveAll(pList *pplist, Datatype x);//删除链表中所有的指定元素

void Insert(pList *pplist,pList pos, Datatype x);//指定位置插入
void Erase(pList *pplist, pNode pos);//指定位置删除
void Sort(pList *pplist);//冒泡排序
void ReverseList(pList *pplist);//倒序链表
#endif

函数功能的实现：

#define _CRT_SECURE_NO_WARNINGS 1
#include "list.h"

void InitList(pList *pplist)
{
assert(pplist);
*pplist = NULL;

}

void DistroyList(pList *pplist)
{
pNode cur = *pplist;
assert(pplist);
while (cur != NULL)
{
pNode p = cur;
cur = cur->next;
free(p);
p = NULL;
}
*pplist = NULL;
}
pNode BuyNode(Datatype x)
{
pNode newNode = (pNode)malloc(sizeof(Node));
newNode->d = x;
newNode->next = NULL;
return newNode;
}
void Print(const pList *pplist)
{
pNode cur = *pplist;
while(cur)
{
printf("%d----> ",cur->d);
cur = cur->next;
}
printf("NULL\n");
}
void PushBack(pList *pplist,Datatype x)
{
pNode newNode = BuyNode(x);
pNode cur = *pplist;

assert(pplist != NULL);

if (*pplist == NULL)  //无结点
{
*pplist = newNode;
return;
}
//有结点
while(cur->next != NULL)
{
cur = cur->next;
}
cur->next = newNode;
}

void PopBack(pList *pplist)
{
pNode cur = *pplist;
assert(pplist);
if (*pplist == NULL)
{
return;
}
if ((*pplist)->next == NULL)
{
free(*pplist);
*pplist = NULL;
return;
}
while(cur->next->next != NULL)
{

cur = cur->next;
}
free(cur->next);
cur->next = NULL;
}

void PushFront(pList *pplist,Datatype x)
{
pNode newNode = BuyNode(x);
assert(pplist);

if (*pplist == NULL)
{
*pplist = newNode;
}
else
{
newNode->next = *pplist;
*pplist = newNode;
}
}

void PopFront(pList *pplist)
{
pNode cur = *pplist;
assert(pplist);
if (*pplist == NULL)
{
return;
}
else if((*pplist)->next == NULL)
{
free(*pplist);
*pplist = NULL;
return;
}
*pplist = cur->next;
free(cur);
cur = NULL;
}

pNode Find(pList *pplist, Datatype x)
{
pNode newNode = *pplist;
assert(pplist);
while(newNode!=NULL)
{
if (newNode->d == x)
{
return newNode;
}
newNode = newNode->next;
}
return NULL;
}
void Remove(pList *pplist, Datatype x)
{
pNode newNode = Find(pplist,x);
assert(pplist);
//未找到
if (newNode == NULL)
{
return;
}
if (newNode->next == NULL)    //元素在尾部
{
PopBack(pplist);
return;
}
if (newNode == *pplist)       //元素在头部
{
PopFront(pplist);
return;
}
newNode->d = newNode->next->d;     //将newNode内的数据与next指针变量改为下个结构体元素内的数据
newNode->next = newNode->next->next;
}
void RemoveAll(pList *pplist, Datatype x)
{
pNode newNode = Find(pplist,x);
assert(pplist);
while (newNode!=NULL)
{
Remove(pplist,x);
newNode = Find(pplist,x);
//ERROR②
//newNode = Find(&newNode,x);

//ERROR①
//newNode->d= newNode->next->d;
//newNode->next = newNode->next->next;
//newNode = Fine(pplist,x);
}
}

//定点插入
void Insert(pList *pplist,pList pos, Datatype x)
{
pNode newNode = BuyNode(x);
assert(pplist);
assert(pos);
if (*pplist == NULL)
{
PushBack(pplist,x);
return;
}
newNode->next = pos->next;
pos->next = newNode;
}

//定点删除
void Erase(pList *pplist, pNode pos)
{
pNode cur = *pplist;
assert(pplist);
assert(pos);

if (*pplist == NULL)
{
return;
}
while (cur && (cur->next != pos))
{
cur = cur->next;
}
if (cur != NULL)
{
cur->next = pos->next;
free(pos);
}
}
//冒泡
void Sort(pList *pplist)
{
Datatype tmp;
pNode p = NULL;
pNode q = NULL;
assert(pplist);

for (p = *pplist; p != NULL; p = p->next)
{
int flag = 1;
for (q = p->next; q != NULL; q = q->next)
{
if (p->d > q->d)
{
flag = 0;

tmp = p->d;
p->d = q->d;
q->d = tmp;
}
}
if (flag == 1)
{
return;
}
}

}
//逆序
void ReverseList(pList *pplist)
{
pNode cur = *pplist;
pNode newhead = *pplist;
assert(pplist);
if ((*pplist == NULL)||((*pplist)->next == NULL))
{
return;
}
/*while(cur->next != NULL)
{
pNode tmp = cur;
cur = cur->next;
cur->next = tmp;
}*/
while (cur->next)
{
pNode tmp = cur->next;
cur->next = tmp->next;
tmp->next = newhead;
newhead = tmp;
}
*pplist = newhead;
}

函数测试源文件是调用各个函数.