数据结构——链表基础

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#pragma once
typedef int DataType;
#include<stdio.h>
typedef struct Node//不带头结点的单链表
{
    struct Node* _pNext;
    DataType _data;
}Node,*PNode;
#include<stdio.h>
#include<assert.h>
#include<malloc.h>
void SListInit(PNode* pHead)
{
    assert(pHead);
    *pHead = NULL;
}
void SListPushBack(PNode* pHead, DataType data)//尾插结点
{
    PNode pNewNode = NULL;
    assert(pHead);
    pNewNode = BuySListNode(data);
    //空
    if (NULL == *pHead)
        *pHead = pNewNode;
    else//非空
    {
        PNode pCur = *pHead;
        while (pCur->_pNext)
            pCur = pCur->_pNext;
        pCur->_pNext = pNewNode;
    }

}
void SListPopBack(PNode* pHead)
{
    assert(pHead);
    if (NULL == *pHead)
        return;
    else if (NULL == (*pHead)->_pNext)
    {
        free(*pHead);
        *pHead = NULL;

    }
    else
    {
        PNode pCur = *pHead;
        while (pCur->_pNext->_pNext)
            pCur = pCur->_pNext;
        free(pCur->_pNext);
        pCur->_pNext = NULL;
    }
}
void DListPushFront(PNode* pHead, DataType data)//头插
{
    PNode pNewNode = NULL;
    assert(pHead);
    pNewNode = BuySListNode(data);
    if (NULL == pNewNode)
        return;
    pNewNode->_pNext = *pHead;
    *pHead = pNewNode;
}
void SListPopFront(PNode* pHead)//头删
{
    PNode pDelNode = NULL;
    assert(pHead);
    if (NULL == *pHead)
        return;
    pDelNode = *pHead;
    *pHead = pDelNode->_pNext;
    free(pDelNode);
}
PNode SListFind(PNode pHead, DataType data)//查找一个结点
{
    PNode pCur = pHead;
    while (pCur)
    {
        if (data == pCur->_data)
            return pCur;
        pCur = pCur->_pNext;
    }
    return NULL;
}
void SListInsert(PNode* pHead, PNode pos, DataType data)
{
    PNode pNewNode = NULL;
    assert(pHead);
    if (NULL == *pHead || NULL == pos)
    {
        return;
    }
    pNewNode = BuySListNode(data);
    if (NULL == pNewNode)
        return;
    pNewNode->_pNext = pos->_pNext;
    pos->_pNext = pNewNode;
}
void SListErase(PNode* pHead, PNode pos)//删除任意位置的元素
{
    assert(pHead);
    if (NULL == *pHeas || NULL == pos)
        return;
    if (pos == *pHead)
        SListPopFront(pHead);
    else
    {
        PNode pCur = *pHead;
        while (pCur&&pCur->_pNext != pos)
            pCur = pCur->_pNext;
        if (pCur)
        {
            pCur->_pNext = pos->_pNext;
            free(pos);
        }
    }
}
void SListDestory(PNode* pHead)
{
    SListClear(pHead);

}
int SListSize(PNode pHead)//链表有效元素的个数
{
    int count = 0;
    PNode pCur = pHead;
    while (pCur)
    {
        count++;
        pCur = pCur->_pNext;
    }
    return count;
}
void SListClear(PNode* pHead)//清除链表
{
    PNode pDelNode = NULL;
    assert(pHead);
    while (*pHead)
    {
        pDelNode = *pHead;
        *pHead = pDelNode->_pNext;
        free(pDelNode);
    }
}
PNode BuySListNode(DataType data)//买一个结点
{
    PNode pNewNode = (PNode)malloc(sizeof(Node));
    {
        if (NULL == pNewNode)
            return NULL;
    }
    pNewNode->_pNext = NULL;
    pNewNode->_data = data;
    return pNewNode;
}
PNode SListBack(PNode pHead)//找链表中最后一个结点的位置
{
    PNode pCur = pHead;
    if (NULL == pHead)
        return NULL;
    while (pCur->_pNext)
        pCur = pCur->_pNext;
    return pCur;
}
void PrintList(PNode pHead)
{
    PNode pCur = pHead;
    while (pCur)
    {
        printf("%d---->", pCur->_data);
        pCur = pCur->_pNext;
    }
    printf("NULL\n");
}