C++实现单链表（类和对象）——简单实现

"test.cpp"

#define _CRT_SECURE_NO_WARNINGS 1
#include <iostream>
using namespace std;
#include "LinkList.h"

void Test()
{
LinkList list;
for (int i = 1;i < 6;i++)
{
list.PushBack(i);
}
cout<<list<<endl;

list.PushFrond(10);
list.PushFrond(9);
list.PushFrond(8);
cout<<list<<endl;

list.PopBack();
list.PopBack();
cout<<list<<endl;
list.PopFrond();
list.PopFrond();
cout<<list<<endl;

LinkListNode* cur = list.Find(9);
if (cur != NULL)
{
cout<<*cur<<endl;
}

list.Insert(list.Find(3),4);
cout<<list<<endl;
list.Insert(list.Find(1),100);
cout<<list<<endl;
list.Insert(list.Find(10),11);
cout<<list<<endl;

list.Remove(list.Find(4));
cout<<list<<endl;
list.Remove(list.Find(10));
cout<<list<<endl;
list.Remove(list.Find(100));
cout<<list<<endl;

}
int main()
{
Test();
system("pause");
return 0;
}

"LinkList.h"

#pragma once
typedef int DataType;
struct LinkListNode
{
LinkListNode(DataType data)
:_data(data)
,_next(NULL)
{}
DataType _data;
LinkListNode* _next;
};

class LinkList
{
friend ostream& operator<<(ostream& os,LinkList& list);
typedef LinkListNode Node;
public:
LinkList()
:_head(NULL)
,_tail(NULL)
{}
~LinkList()
{
Node* cur = _head;
while (cur)
{
Node* tmp = cur;
cur = cur->_next;
delete tmp;
tmp = NULL;
}
}
public:
void PushBack(const DataType data)
{
if ((_head == NULL) && (_tail == NULL))
{
_head = new Node(data);
_tail = _head;
}
else
{
Node* tmp = new Node(data);
_tail->_next = tmp;
_tail = _tail->_next;
}
}
void PushFrond(const DataType data)
{
Node* cur = new Node(data);
if ((_head == NULL) && (_tail == NULL))
{
_head = cur;
_tail = _head;
}
else
{
cur->_next = _head;
_head = cur;
}
}
void PopBack()
{
if ((_head == NULL) && (_tail == NULL))
{
cout<<"链表已空"<<endl;
return;
}
else
{
Node* del = _head;
Node* delprev = NULL;
while (del != _tail)
{
delprev = del;
del = del->_next;
}
_tail = delprev;
_tail->_next = NULL;//尾指针的下一个位置一定要记得置空，否则程序中断
delete del;
del = NULL;
}
}
void PopFrond()
{
if ((_head == NULL) && (_tail == NULL))
{
cout<<"链表已空"<<endl;
}
else
{
Node* del = _head;
_head = _head->_next;
delete del;
del = NULL;
}
}
Node* Find(const DataType data)
{
if ((_head == NULL) && (_tail == NULL))
{
cout<<"List is Null"<<endl;
return NULL;
}
else
{
Node* cur = _head;
while (cur)
{
if (cur->_data == data)
{
return cur;
}
else
{
cur = cur->_next;
}
}
}
return NULL;
}
//在某一个节点的后面插入一个节点
void Insert(Node* cur,const DataType data)
{
Node* tmp = new Node(data);
if (cur == NULL)
{
_head = tmp;
_tail = _head;
}
//这个节点是尾结点的情况
if (cur == _tail)
{
cur->_next = tmp;
_tail = tmp;
}
else
{
tmp->_next = cur->_next;
cur->_next = tmp;
}
}
//删除当前节点
void Remove(Node* cur)
{
if (cur == NULL)
{
cout<<"no find"<<endl;
return;
}
Node* tmp = _head;
if (cur == _head)
{
Node* del = _head;
_head = _head->_next;
delete del;
del = NULL;
}
else if (cur == _tail)
{
while (tmp->_next != cur)
{
tmp = tmp->_next;
}
_tail = tmp;
_tail->_next = NULL;
delete cur;
cur = NULL;
}
else
{
//找到删除节点的前一个位置
while (tmp->_next == cur)
{
tmp = tmp->_next;
}
tmp->_next = cur->_next;
delete cur;
cur = NULL;
}
}
private:
Node* _head;//头指针
Node* _tail;//尾指针
};

ostream& operator<<(ostream& os,LinkListNode& node)
{
os<<node._data<<" ";
return os;
}
ostream& operator<<(ostream& os,LinkList& list)
{
LinkListNode* cur = list._head;
while (cur)
{
os<<*cur<<" ";
cur = cur->_next;
}
return os;
}