单项链表笔记

#ifndef LINKLIST_H
#define LINKLIST_H
typedef struct _LISTNODE
{
void* data;
_LISTNODE* next;
}LISTNODE;
typedef struct _LINKLIST
{
LISTNODE* head;
int size;
}LINKLIST;
//打印函数指针
typedef void(*PRINTLINKNODE)(void*);
//初始化链表
LINKLIST* initLinkList();
//指定位置插入数据
void insert(LINKLIST* list,int pos,void* data);
//指定位置删除数据
void removeByPos(LINKLIST* list, int pos);
//获得链表大小
int size(LINKLIST* list);
//查找
int findLinkList(LINKLIST* list, void* data);
//返回第一个节点
void* frontList(LINKLIST* list);
//释放链表
void freeLinkList(LINKLIST* list);
//打印链表
void printLinkList(LINKLIST* list, PRINTLINKNODE print);
#endif

#include<>
#include "linklist.h"
using namespace std;
//初始化链表
LINKLIST* initLinkList()
{
LINKLIST* listLink = new LINKLIST;
listLink->size = 0;
//头结点不保存数据
listLink->head = new LISTNODE;
listLink->head->data = NULL;
listLink->head->next = NULL;
return listLink;
}
//指定位置插入数据
void insert(LINKLIST* list, int pos, void* data)
{
if (list == NULL)
{
return;
}
if (data == NULL)
{
return;
}
//友好的处理,pos越界
if (pos < 0 || pos>list->size)
{
pos = list->size;
}
//创建新的节点
LISTNODE* newNode = new LISTNODE;
newNode->data = data;
newNode->next = NULL;
//找节点,辅助指针变量
LISTNODE* pCurrent = list->head;
for (int i = 0; i < pos; i++)
{
pCurrent = pCurrent->next;
}
//新节点插入链表
newNode->next = pCurrent->next;
pCurrent->next = newNode;
list->size++;
}
//指定位置删除数据
void removeByPos(LINKLIST* list, int pos)
{
if (list == NULL)
{
return;
}
if (pos < 0 || pos >= list->size)
{
return;
}
LISTNODE* pCurrent = list->head;
for (int i = 0; i < pos; i++)
{
pCurrent = pCurrent->next;
}
LISTNODE* pDel = pCurrent->next;
pCurrent->next = pDel->next;
delete pDel;
list->size--;
}
//获得链表大小
int size(LINKLIST* list)
{
return list->size;
}
//查找
int findLinkList(LINKLIST* list, void* data)
{
if(listNULL)
{
return -1;
}
if (data == NULL)
{
return -1;
}
//遍历查找
LISTNODE* pCurrent = list->head;
int i = 0;
while (pCurrent != NULL)
{
if(pCurrent->datadata)
{
break;
}
i++;
pCurrent = pCurrent->next;
}
return i;
}
//返回第一个节点
void* frontList(LINKLIST* list)
{
return list->head->next->data;
}
//释放链表
void freeLinkList(LINKLIST* list) {
if (list == NULL)
{
return;
}
LISTNODE* pCurrent = list->head;
while (pCurrent != NULL)
{
//缓存下一个节点
LISTNODE* pNext = pCurrent->next;
delete pCurrent;
pCurrent = pNext;
}
//释放链表内存
delete list;
}
//打印链表
void printLinkList(LINKLIST* list, PRINTLINKNODE print)
{
if (list == NULL)
{
return;
}
LISTNODE* pCurrent = list->head->next;
while (pCurrent != NULL)
{
print(pCurrent->data);
pCurrent = pCurrent->next;
}
}
typedef struct _PERSON
{
char name[64];
int age;
int score;
}PERSON;
//打印函数
void myPrint(void* data)
{
PERSON* pP = (PERSON*)data;
std::cout << pP->name << " " << pP->age << " " << pP->score << endl;
}
int main()
{
LINKLIST* list = initLinkList();
//创建数据
PERSON P1 = { "AAA",19,100};
PERSON P2 = { "BBB",18,80 };
PERSON P3 = { "CCC",17,40 };
PERSON P4 = { "DDD",22,77 };
PERSON P5 = { "EEE",20,99 };
//数据插入链表
insert(list, 0, &P1);
insert(list, 0, &P2);
insert(list, 0, &P3);
insert(list, 0, &P4);
insert(list, 0, &P5);
printLinkList(list, myPrint);
cout << "="<<endl;
//删除3
removeByPos(list, 3);
printLinkList(list, myPrint);
cout << "=" << endl;
PERSON* RET = (PERSON*)frontList(list);
cout << RET->name << " " << RET->age << " " << RET->score<<endl;
return 0;
}