🖊作者 : Djx_hmbb
📘专栏 : 数据结构
😆今日分享 : “Onc in a blu moon” : “罕见的,千载难逢的” (出现在19世纪,指的是"在一个月内出现的第二次圆月”，这种现象每隔32个月发生一次。)

✔单链表的功能实现:

🔎申请一个结点空间 :

//为单链表申请一个结点空间
SLT* SLTBuy(SLTdataType x)
{SLT* newNode = (SLT*)malloc(sizeof(SLT));if (newNode == NULL) {perror("malloc fail:");exit(-1);}else{newNode->data = x;newNode->next = NULL;}return newNode;
}

🔎构建n个链表 :

//构建n个链表
SLT* SLTCreate(SLTdataType x)
{SLT* phead = NULL, * ptail = NULL;for (int i = 0; i < x; i++){SLT* newNdoe = SLTBuy(i);if (phead == NULL){phead = ptail = newNdoe;}else {ptail->next = newNdoe;ptail = newNdoe;}}return phead;
}

🔎打印链表 :

//打印链表
void SLTPrint(SLT* phead)
{SLT* cur = phead;while (cur != NULL){printf("%d ",cur->data);cur = cur->next;}puts("NULL\\n");
}

🔎尾插 :

//尾插!!!!!!!!!!!!!!!!!!要用取地址!!!!!!!!!!!
void SLTPushBack(SLT** pphead, SLTdataType x) 
{SLT* newNode=SLTBuy(x);if (*pphead == NULL){*pphead = newNode;}else{SLT* ptail = *pphead;//找尾结点while (ptail->next){//移动指针ptail = ptail->next;}//将新建的结点插入尾结点ptail->next = newNode;}}

🔎尾删 :

//尾删
void SLTPopBack(SLT** pphead)
{assert(*pphead);//检查链表头结点是否为空//法一:SLT* ptail = (*pphead)->next;SLT* cur = *pphead;//判断头结点是否为空if(*pphead != NULL){//判断第二个节点是否为空(ptail)if ((*pphead)->next != NULL){ //找尾//SLT* ptail = (*pphead)->next;while (ptail->next){cur = ptail;ptail = ptail->next;}//找到尾后,释放空间,并将前面的一个结点置为空free(ptail);cur->next = NULL;}else{free(*pphead);*pphead = NULL;}}else{free(*pphead);*pphead = NULL;}法二://SLT* ptail = *pphead;找尾//if (ptail->next)//{//	while (ptail->next->next)//{//	ptail = ptail->next;//}找到尾后,释放空间,并将前面的一个结点值为空//free(ptail->next);//ptail->next = NULL;//}//else//{//	free(*pphead);//	*pphead = NULL;//}}

🔎头插 :

//头插
void SLTPushFront(SLT** pphead, SLTdataType x)
{SLT* newNode = SLTBuy(x);if (*pphead==NULL){*pphead = newNode;}else{SLT* ptail = (*pphead);//SLT* cur = (*pphead)->next;*pphead = newNode;newNode->next = ptail;ptail = *pphead;}
}

🔎头删 :

//头删
void SLTPopFront(SLT** pphead)
{if (*pphead == NULL){//释放原空间free(*pphead);(*pphead) = NULL;}else{//删除SLT* ptail = (*pphead)->next;if (ptail != NULL){(*pphead) = ptail;}else{free(*pphead);(*pphead) = NULL;}}
}

🔎查找 :

//查找
SLT* SLTFind(SLT* phead, SLTdataType x)
{assert(phead);SLT* cur = phead;while (cur != NULL){//找xwhile (cur->data != x){cur = cur->next;}//找到后,返回地址return cur;}return NULL;
}

🔎在pos位置后插入x :

//在pos位置后插入x
void SLTInsertAfter(SLT* pos, SLTdataType x)
{assert(pos);//判断pos位置是否存在SLT* newNode = SLTBuy(x);newNode->next = pos->next;pos->next = newNode;
}

🔎在pos位置前插入x :

//在pos位置前插入x
void SLTInsertFront(SLT** pphead, SLT* pos, SLTdataType x)
{assert(pos);if (*pphead == pos){SLTPushFront(pphead,x);}else{SLT* prev = *pphead;//找到pos的前一个结点while (prev->next != pos){prev = prev->next;}//找到后,添加节点SLT* newNode = SLTBuy(x);prev->next = newNode;newNode->next = pos;}
}

🔎删除pos位置后一个指针 :

//删除pos位置后一个指针
void SLTDeleteAfter(SLT* pos)
{assert(pos);if (pos->next == NULL){return ;}else{pos->next = pos->next->next;}
}

🔎删除pos位置的指针 :

//删除pos位置的指针
void SLTDPosDelete(SLT** pphead, SLT* pos)
{//assert(*pphead);//不用断言,如果plist为空,则pos一定为空;可是plist不为空,但是pos可能为空!!!assert(pos);if (pos == *pphead){SLTPopFront(pphead);}else{SLT* prev = *pphead;//找到pos前一个节点while (prev->next != pos){prev = prev->next;}//删除pos结点prev->next = pos->next;free(pos);//pos = NULL;//不用置空,无意义:置空的是形参}
}

🔎释放空间 :

//释放空间
void SLTDestory(SLT** pphead)
{//结点是一个一个申请的,所以释放的时候也需要一个一个释放!!!// 错误示范://free(*pphead);//(*pphead)->next = NULL;//正确:SLT* cur = *pphead;while (cur != NULL){SLT* next = cur->next;free(cur);cur = next;}*pphead = NULL;//头指针此时为野指针，需要置空
}

✔头文件(详情):

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#include<assert.h>#define SLTdataType int//定义结构体
typedef struct SLTnode
{SLTdataType data;struct  SLTnode* next;
}SLT; //为结点申请一个空间
SLT* SLTBuy(SLTdataType x);//构建n个链表
SLT* SLTCreate(SLTdataType x);//打印链表
void SLTPrint(SLT* phead);//尾插
void SLTPushBack(SLT** pphead,SLTdataType x);//尾删
void SLTPopBack(SLT** pphead);//头插
void SLTPushFront(SLT** pphead, SLTdataType x);//头删
void SLTPopFront(SLT** pphead);//查找
SLT* SLTFind(SLT* phead, SLTdataType x);//在pos位置后插入x
void SLTInsertAfter(SLT* pos, SLTdataType x);//在pos位置前插入x
void SLTInsertFront(SLT** pphead,SLT* pos, SLTdataType x);//删除pos位置后一个指针
void SLTDeleteAfter(SLT* pos);//删除pos位置的指针
void SLTDPosDelete(SLT** pphead, SLT* pos);//释放空间
void SLTDestory(SLT** pphead);

✔测试文件(详情):

#define _CRT_SECURE_NO_WARNINGS
#include"SLTNode.h"test01()
{SLT* b1 = SLTBuy(1);SLT* b2 = SLTBuy(2);SLT* b3 = SLTBuy(3);b1->next = b2;b2->next = b3;SLTPrint(b1);
}test02()
{SLT* plist= SLTCreate(3);SLTPrint(plist);
}test03()
{SLT* plist=SLTCreate(3);//0 1 2/*int x = 0;printf("请输入尾插的数字:");scanf("%d",&x);SLTPushBack(&plist,x);SLTPrint(plist);*///SLTPopBack(&plist);//0 1//SLTPrint(plist);//SLTPopBack(&plist);//0//SLTPrint(plist);//SLTPopBack(&plist);//NULL//SLTPrint(plist);
}
test04()
{SLT* plist = SLTCreate(3);//0 1 2//int x = 0;//printf("请输入头插的值:");//scanf("%d",&x);SLTPushFront(&plist,3);SLTPrint(plist);SLTPopFront(&plist);SLTPrint(plist);//0 1 2SLTPopFront(&plist);SLTPrint(plist);//1 2SLTPopFront(&plist);SLTPrint(plist);// 2SLTPopFront(&plist);SLTPrint(plist);//NULL
}
test05()
{SLT* plist = NULL;SLTPushFront(&plist, 3);SLTPushFront(&plist, 2);SLTPushFront(&plist, 1);SLTPushFront(&plist, 0);SLTPrint(plist);//0 1 2 3 NULLSLT* pos = SLTFind(plist,3);printf("%p\\n",pos);//000002866BDFE0E0SLTInsertAfter(pos,12);SLTPrint(plist);//0 1 2 3 12 NULLSLTInsertFront(&plist,pos,11);SLTPrint(plist);//0 1 2 11 3 12 NULLSLTDeleteAfter(pos);SLTPrint(plist);//0 1 2 11 3 NULLpos = SLTFind(plist,0);SLTDPosDelete(&plist,pos);SLTPrint(plist);//0 1 2 11 NULL}
main()
{test05();system("pause");return 0;
}

家人们,点个再走呗~