【 数据结构（C语言）】线性表——单链表和单循环链表

1.线性链表：用任意的存储单元存储线性表的数据元素（这组存储单元可以是连续的也可以是不连续）

2.动态链表和静态链表的区别

• 静态链表是用数组实现的，是顺序的存储结构，在物理地址上是连续的，而且需要预先分配大小。
• 动态链表是用申请内存函数（C是malloc,C++是new）动态申请内存的，所以在链表的长度上没有限制。动态链表因为是动态申请内存的，所以每个节点的物理地址不连续，要通过指针来顺序访问。

3.单链表基本功能实现

#include <bits/stdc++.h>
using namespace std;
#define ElemType  int
#define Status int
#define ERROR -1
#define OK 1

typedef struct LNode
{
   ElemType data;
   struct  LNode *next;
}LNode ,*LinkList;
LinkList CreateListHead_L(int n)///* 头插入
{
    LinkList L = (LinkList)malloc(sizeof(LNode));
    L->next = NULL;
    while (n--)
    {
        LinkList newnode = (LinkList)malloc(sizeof(LNode));
        scanf("%d",&newnode->data);
        newnode->next = L->next;
        L->next = newnode;
    }
    return L;
}
LinkList CreateListTail_L(int n)///尾插入
{
    LinkList L = (LinkList)malloc(sizeof(LNode));
    LinkList last = (LinkList)malloc(sizeof(LNode));
    L->next = NULL;
    last = L;
    while (n--)
    {
        ElemType e;
        scanf("%d",&e);
        LinkList newnode = (LinkList)malloc(sizeof(LNode));
        newnode->data = e;
        last->next = newnode;
        newnode->next = NULL;
        last = newnode;
    }
    return L;
}
Status GetElem_L(LinkList &L,int i,ElemType &e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < i)
    {
        index = index->next;
        ++ct;
    }
    if (!index || ct > i) return ERROR;
    e = index->data;
    return OK;
}
Status ListInsert_L(LinkList &L,int i,ElemType e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < (i-1))
    {
        index = index->next;
        ++ct;
    }
    if (!index || ct > i -1) return ERROR;
    LinkList newnode = (LinkList)malloc(sizeof(LNode));
    newnode->data = e;
    newnode->next = index->next;
    index->next = newnode;
    return OK;
}
Status ListDeteleByPos_L(LinkList &L,int i,ElemType &e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < i-1)
    {
        index = index->next;
        ++ct;
    }
    if (!(index->next) || ct > i-1) return ERROR;
    LinkList tmp  = index->next;
    index->next = tmp->next;
    e = tmp->data;
    free(tmp);
    return OK;
}
Status ListDeteleByVal_L(LinkList &L,ElemType e)
{
    LinkList index = L->next,pri = L;
    while (index) /// 注意：判断的如果是 pri pri 是最后一个元素的时候 index 已经超出链表
    {
        if (index->data == e)
        {
            pri->next = index->next;
            free(index);
            index = pri->next;
        }
        else
        {
            pri = pri->next;
            index = index->next;
        }
    }
    return OK;
}
int GetLength(LinkList &L)
{
    int len = 0;
    LinkList index = L->next;
    while (index)
    {
       index = index->next;
       len++;
    }
    return len;
}
LinkList ListReverse(LinkList &L)
{
    LinkList a = L->next;
    LinkList b = a->next;
    LinkList c = b->next;
    a->next = NULL;
    int len = GetLength(L);
    while (len--)
    {
        b->next  = a;
        c = b;
        b = a;
        if(!a)
        {
            L->next=a;
        }
        else c=c->next;
    }
    return L;
}
void TrverseLinklist(LinkList &L)///* 注意：这里是带头指针的链表
{
    LinkList  index = L->next;
    for (;index!= NULL; index = index->next)
    {
        cout<<index->data<<" ";
    }
    cout<<endl;
}

4.单循环链表

注意：只是将单链表中的最后一个结点的指针是指着头结点的，形成循环

#include <bits/stdc++.h>
using namespace std;
#define ElemType  int
#define Status int
#define ERROR -1
#define OK 1

typedef struct LNode
{
   ElemType data;
   struct  LNode *next;
}LNode ,*LinkList;
LinkList CreateListHead_L(int n)///* 头插入
{
    LinkList L = (LinkList)malloc(sizeof(LNode));
    L->next = L;/// 改：
    while (n--)
    {
        LinkList newnode = (LinkList)malloc(sizeof(LNode));
        scanf("%d",&newnode->data);
        newnode->next = L->next;
        L->next = newnode;
    }
    return L;
}
LinkList CreateListTail_L(int n)///尾插入
{
    LinkList L = (LinkList)malloc(sizeof(LNode));
    LinkList last = (LinkList)malloc(sizeof(LNode));
    L->next = L;
    last = L;
    while (n--)
    {
        ElemType e;
        scanf("%d",&e);
        LinkList newnode = (LinkList)malloc(sizeof(LNode));
        newnode->data = e;
        last->next = newnode;
        newnode->next = L;/// 改：
        last = newnode;
    }
    return L;
}
Status GetElem_L(LinkList &L,int i,ElemType &e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < i)
    {
        index = index->next;
        ++ct;
    }
    if (!index || ct > i) return ERROR;
    e = index->data;
    return OK;
}
Status ListInsert_L(LinkList &L,int i,ElemType e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < (i-1))
    {
        index = index->next;
        ++ct;
    }
    if (!index || ct > i -1) return ERROR;
    LinkList newnode = (LinkList)malloc(sizeof(LNode));
    newnode->data = e;
    newnode->next = index->next;
    index->next = newnode;
    return OK;
}
Status ListDeteleByPos_L(LinkList &L,int i,ElemType &e)
{
    LinkList index = L->next;
    int ct = 1;
    while (index && ct < i-1)
    {
        index = index->next;
        ++ct;
    }
    if (!(index->next) || ct > i-1) return ERROR;
    LinkList tmp  = index->next;
    index->next = tmp->next;
    e = tmp->data;
    free(tmp);
    return OK;
}
Status ListDeteleByVal_L(LinkList &L,ElemType e)
{
    LinkList index = L->next,pri = L;
    while (index != L) /// 改：将循环条件改了
    {
        if (index->data == e)
        {
            pri->next = index->next;
            free(index);
            index = pri->next;
        }
        else
        {
            pri = pri->next;
            index = index->next;
        }
    }
    return OK;
}
int GetLength(LinkList &L)
{
    int len = 0;
    LinkList index = L->next;
    while (index != L)/// 改：将循环条件改了
    {
       index = index->next;
       len++;
    }
    return len;
}
void TrverseLinklist(LinkList &L)///* 注意：这里是带头指针的链表
{
    LinkList  index = L->next;
    for (;index!= L; index = index->next)/// 改：将循环条件改了
    {
        cout<<index->data<<" ";
    }
    cout<<endl;
}