带头结点单链表的内存分布情况

 

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头文件

#pragma once
//带头节点的单链表
//单链表尾节点的next为NULL
//List为一条链表；Node* 一个节点的地址
typedef struct Node
{int data;//数据Node *next;//下一个节点的地址
}Node ,*List ;//List == Node *//初始化
void InitList(List plist);//头插法
bool Insert_head(List plist,int val);//尾插法
bool Insert_tail(List plist,int val);//在pos下标插入数据val
bool Insert_pos(List plist,int pos,int val);//查找，找到返回节点地址，没有找到返回NULL
Node *Search(List plist,int key);//删除第一个key对应的节点
bool Delete(List plist,int key);//删除第一个数据节点，并通过rtval获得删除的值
bool Delete_head(List plist,int *rtval);//删除最后一个数据节点，并通过rtval获得删除的值
bool Delete_tail(List plist,int *rtval);//获取长度，统计数据节点的个数
int GetLength(List plist);//判空
bool IsEmpty(List plist);//清除所以数据
void Clear(List plist);//销毁所有节点
void Destroy(List plist);//打印
void Show(List plist);

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cpp文件

#include<stdio.h>
#include<assert.h>
#include<stdlib.h>
#include"list.h"//初始化
void InitList(List plist)
{assert(plist != NULL);plist->next = NULL;
}//头插法
bool Insert_head(List plist,int val)
{assert(plist != NULL);Node *p = (Node*)malloc(sizeof(Node));p->data = val;p->next = plist->next; plist->next = p;return true;
}//尾插法
bool Insert_tail(List plist,int val)
{assert(plist != NULL);Node * p = (Node*)malloc(sizeof(Node));assert( p != NULL);if(p == NULL){return false;}Node *q;for(q=plist;q->next != NULL;q = q->next);//把p 插到 q 的后边p->next = q->next;q->next = p;p->data = val;//p->next = NULL;return true;}//在pos下标插入数据val
bool Insert_pos(List plist,int pos,int val)
{if(pos < 0){return false;}Node *p = (Node*) malloc (sizeof(Node));Node *q = plist;int i = 0;for(;q->next!= NULL && i<pos;i++,q = q->next);if(i< pos )//判断是否连续{return false;}p->next = q ->next;q->next = p;p->data = val;
}//查找，找到返回节点地址，没有找到返回NULL
Node* Search(List plist,int key)
{Node *p;for(p =plist->next;p != NULL;p=p->next){if(p->data == key ){return p ;}}//return false;return NULL;
}
//查找key的前趋节点
static Node *SearchPri(List plist,int key)
{Node* p = (Node*) malloc (sizeof(Node));for(p = plist;p ->next != NULL; p = p->next){if(p->data == key){return p;}}return NULL;
}
//删除第一个key对应的节点
bool Delete(List plist,int key)
{Node *p;p = SearchPri(plist, key);//p是查找的key对应的前驱if(p == NULL){return false;}Node* q = p->next;//q 指向将要删除的节点p->next = q->next;//将q从链表中剔除free(q);//释放q
}//删除第一个数据节点，并通过rtval获得删除的值
bool Delete_head(List plist,int *rtval)
{assert(plist != NULL);if(plist != NULL || plist->next == NULL){return false;}if(rtval != NULL){*rtval = plist->data;}Node * p = plist ->next;plist->next = p->next;free(p);}//删除最后一个数据节点，并通过rtval获得删除的值
bool Delete_tail(List plist,int *rtval)//******************************
{assert(plist != NULL);if(plist == NULL || plist->next == NULL){return false;}Node *p;for(p =plist;p ->next!= NULL; p = p->next);if(rtval != NULL){*rtval = p->next->data;}p ->next = NULL;free(p);return true;
}//获取长度，统计数据节点的个数
int GetLength(List plist)
{int length = 0;for(Node *p =plist->next;p != NULL ;p = p->next){length ++;}return length;
}//判空
bool IsEmpty(List plist)
{assert(plist != NULL);if(plist == NULL){return false;}return plist->next == NULL;
}//清除所有数据
void Clear(List plist)
{Destroy(plist);
}//销毁所有节点
void Destroy(List plist)
{assert(plist != NULL);if(plist == NULL){return ;}while(plist ->next != NULL){Node *p = plist->next;plist ->next= p->next;free(p);}
}//打印
void Show(List plist)
{assert(plist != NULL);if(plist == NULL){return ;}for(Node*p = plist ->next;p != NULL;p = p->next){printf("%d ",p->data);}printf("\n");
}

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主函数

#include<stdio.h>
#include"list.h"int main()
{Node list1;Node list2;InitList(&list1);for(int i= 0;i<10;i++){Insert_tail( &list1,i);}Show(&list1);InitList(&list2);for(int i= 0;i<10;i++){Insert_head( &list2,i);}Show(&list2);int rt = -1;printf("%d\n",Delete_tail(&list2,&rt));printf("%d\n",&rt);Destroy(&list1);Show(&list1);Destroy(&list2);Show(&list2);return 0;
}