数据结构之链表(单链表、循环链表)

链接方式存储的线性表简称为链表。以“结点的序列”表示线性表称作单链表。用一组任意的存储单元来存放线性表的结点（这组存储单元既可以是连续的，也可以是不连续的）。链表中结点的逻辑次序和物理次序不一定相同。为了能正确表示结点间的逻辑关系，在存储每个结点值的同时，还必须存储指示其后继结点的地址（或位置）信息。单链表是一种链式存取的数据结构，用一组地址任意的存储单元存放线性表中的数据元素。链表中的数据以结点表示的，每个结点的构成：元素 + 指针(指示其后元素的存储位置。data域--存放结点值的数据域；next域--存放结点的直接后继的地址（位置）的指针域。

带头节点单链表
函数实现

头文件

#pragma oncetypedef struct Node{    int data;//数据域    struct Node *next;//指向下一个节点}Node,*List;void InitList(List plist);bool Insert_Head(List plist,int val);//头插bool Insert_Tail(List plist,int val);//尾插Node *Search(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);

基本操作的函数实现

#include <stdio.h>#include <stdlib.h>#include <assert.h>#include "list.h"void InitList(List plist)//初始化单链表{    assert(plist != NULL);    plist->next = NULL;}bool Insert_Head(List plist,int val)//头插{    Node *p = (Node *)malloc(sizeof(Node));    p->data = val;    p->next = plist->next;      return true;}bool Insert_Tail(List plist,int val)//尾插{    Node *p = (Node *)malloc(sizeof(Node));    p->data = val;    Node *q;    for(q=plist;q->next!=NULL;q=q->next);    p->next = q->next//将p插入在q的后面    q->next = p;    return true;}Node *Search(List plist,int key)//查找{    Node *p;    for(p = plist->next;p!=NULL;p=p->next)    {        if(p->data == key)        {            return p;        }    }    return NULL;}bool Delete(List plist,int key)//删除{    Node *p;    for(p=plist->next;p!=NULL;p=p->next)    {        if(p->next->data == key)        {            p->next = p->next->next;            p->data = p->next->data;        }        return true;    }    return false;}bool IsEmpty(List plist)//判空{    if(plist->next==NULL)    {        return true;    }    return false;}int GetLength(List plist){    int num;    for(num=0;plist->next!=NULL;num++)    {        ;    }    return num;}Show(List plist)//打印函数{    for(Node *p=plist->next;p!=NULL;p=p->next)    {        printf("%d ",p->data);    }    printf("\n");}void Clear(List plist)//清空{    Destroy(plist);}void Destroy(List plist)//摧毁{    Node *p;    while(plist->next != NULL)    {        p = plist->next;        plist->next = p->next;        free(p);    }    /*       方法二    Node *p = plist->next;    //Node *q = p->next;//bug    Node *q;    while(p != NULL)    {        q = p->next;        free(p);        p = q;    }    plist->next = NULL;    */}void Revers(List plist){    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;        p->next = plist->next;        plist->next = p;        p = q;    }int mian(){    Node plist;    InitList(&plist);    for (int i=0;i<5;i++)    {        Insert_Tail(&plist,i);    }    //Revers(&plist);    //Delete(&plist, 2);    Show(&plist);    return 0;}

带尾节点的循环链表
代码实现

#include <stdio.h>#include <stdlib.h>void InitList(CList plist){    assert(plist != NULL);    if(plist == NULL)    {        return ;    }    plist->next = plist;}bool Insert_Head(CList plist,int val){    CNode *p = (CNode *)malloc(sizeof(CNode));    assert(p != NULL);    p->data = val;    p->next = plist->next;    plist->next = p;    return true;}void Show(CList plist){    for(CNode *p=plist->next;p!=plist;p=p->next)    {        printf("%d ",p->data);    }    printf("\n");}