单链表的基本操作

今天我们来看看单链表的基本操作：初始化，插入（头插、尾插），查找，删除，判空，求长，摧毁，逆置。

.cpp:

#include <stdio.h>#include <stdlib.h>#include <assert.h>#include "list.h"void InitList(List plist){assert(plist != NULL);plist->next = NULL;//plist->data不用操作}//头插bool Insert_Head(List plist,int val){Node *p = (Node *)malloc(sizeof(Node));p->data = val;p->next = plist->next;plist->next = p;return true;}//尾插bool Insert_Tail(List plist,int val){Node *p = (Node *)malloc(sizeof(Node));p->data = val;Node *q;for(q=plist;q->next!=NULL;q=q->next) ;//将p插入在q的后面p->next = q->next;//p->next = NULL;q->next = p;return true;}Node *Search(List plist,int key){for(Node *p=plist->next;p!=NULL;p=p->next){if(p->data == key){return p;}}return NULL;}//查找key的前驱static Node *SearchPri(List plist,int key){for(Node *p=plist;p->next!=NULL;p=p->next){if(p->next->data == key){return p;}}return NULL;}bool Delete(List plist,int key){Node *p = SearchPri(plist,key);if(p == NULL){return false;}Node *q = p->next;p->next = q->next;//将q从链表中剔除//p->next = p->next->next;free(q);return true;}bool IsEmpty(List plist){return plist->next == NULL;}int GetLength(List plist){int count = 0;for(Node *p=plist->next;p!=NULL;p=p->next){count++;}return count;}void Show(List plist){for(Node *p=plist->next;p!=NULL;p=p->next){printf("%d ",p->data);}printf("\n");}void Clear(List plist){Destroy(plist);}void Destroy(List plist){Node *p;while(plist->next != NULL)//第一种方法总删除第一个数据节点{p = plist->next;plist->next = p->next;free(p);}/*Node *p = plist->next;//第二种方法//Node *q = p->next;//bugNode *q;while(p != NULL){q = p->next;free(p);p = q;}plist->next = NULL;*/}void Revers(List plist)//逆置{//第一种方法头插的思想if(plist==NULL || plist->next==NULL ||   plist->next->next==NULL){return ;}Node *p = plist->next;Node *q;plist->next = NULL;//while(p != NULL){q = p->next;//将p头插进链表p->next = plist->next;plist->next = p;p = q;}//第二种方法#if 0/*if(plist->next->next==NULL ||   plist==NULL || plist->next==NULL    )*///errorif(plist==NULL || plist->next==NULL ||   plist->next->next==NULL){return ;}Node*p = plist->next;Node *q = p->next;Node *s;p->next = NULL;while(q != NULL){s = q->next;q->next = p;p = q;q = s;}plist->next = p;#endif}

.h:

#pragma once//带头节点的单链表typedef struct Node{int data;//数据域struct Node *next;//指向下一个节点}Node,*List;//List == Node*void InitList(List plist);//Node *plist//头插bool Insert_Head(List plist,int val);//尾插bool Insert_Tail(List plist,int val);Node *Search(List plist,int key);//List Node *Search_before(List plist,int key);bool Delete(List plist,int key);bool IsEmpty(List plist);int GetLength(List plist);void Show(List plist);void Clear(List plist);void Destroy(List plist);void Revers(List plist);