【数据结构】线性表之链表--C++语言描述

#include <iostream>
using namespace std;

template<typename T>
class CList;

template<class T>
class Node
{
friend CList<T>;
private:
T m_data;
Node *m_pNext;
};

template<class T>
class CList
{
public:
CList();
~CList();

bool IsEmpty();
void Append(const T &data);
void Delete(const int &pos);
void Print();
int GetLength();
T Find(const int &pos);
void Insert(const int &pos,const T &data);

private:
Node<T> *m_pHead;
Node<T> *m_pEnd;
int m_len;

void Create();
void Destroy();
};
//为头结点分配空间
template<class T>
void CList<T>::Create()
{
m_pHead = new Node<T>;
m_pEnd = new Node<T>;

m_pHead->m_pNext = NULL;
m_pEnd->m_pNext = m_pHead->m_pNext;

m_len = 0;
}

template<class T>
CList<T>::CList()
{
Create();
}
//删除所有结点
template<class T>
void CList<T>::Destroy()
{
Node<T> *pF = m_pHead->m_pNext;
Node<T> *pT;
while(pF)
{
pT = pF;
pF = pF->m_pNext;
delete pT;
}
}

template<class T>
CList<T>::~CList()
{
Destroy();
}
//判断是否为空
template<class T>
bool CList<T>::IsEmpty()
{
if(!m_pHead->m_pNext)
{
return true;
}
else
{
return false;
}
}
//从表的最后加入一个元素
template<class T>
void CList<T>::Append(const T &data)
{
Node<T> *pT = new Node<T>;
pT->m_data = data;
pT->m_pNext = NULL;

if(!m_pHead->m_pNext)
{
m_pHead->m_pNext = pT;
}
else
{
(m_pEnd->m_pNext)->m_pNext = pT;
}
m_pEnd->m_pNext = pT;
++m_len;

}
//删除一个元素
template<class T>
void CList<T>::Delete(const int &pos)
{
if(pos < 0 || pos < m_len)
{
cout<<"位置不合法"<<endl;
return;
}
Node<T> *pPre = NULL;//存放前一个结点
Node<T> *pBehind = NULL;//存放后一个结点
Node<T> *pT = m_pHead->m_pNext;//目标结点
int ix = -1;
while(pT)
{
++ix;
if(ix == pos - 1 - 1)
{
pPre = pT;
}
else if(ix == pos - 1)
{
pBehind = pT->m_pNext;
break;
}
pT = pT->m_pNext;
}

if(!pPre)//如果指针为空则说明pos是指第一个元素
{
delete pT;
m_pHead->m_pNext = pBehind;
--m_len;
return;
}
if(!pBehind)//如果指针为空则说明pos是指最后一个元素
{
m_pEnd = pPre;
delete pT;
}
pPre->m_pNext = pBehind;

--m_len;
}
//输出所有数据
template<class T>
void CList<T>::Print()
{
Node<T> *pT = m_pHead->m_pNext;
while(pT)
{
cout<<pT->m_data<<",";
pT = pT->m_pNext;
}
cout<<endl;
}

template<class T>
int CList<T>::GetLength()
{
return m_len;
}
//查找数据
template<class T>
T CList<T>::Find(const int &pos)
{
if(pos <= 0)
{
cout<<"输入不合法"<<endl;
return NULL;
}
if(pos > m_len)
{
cout<<"超出表长"<<endl;
return NULL;
}
int i = 0;
Node<T> *pT = m_pHead->m_pNext;
while(pT)
{
++i;
if(i == pos)
{
return pT->m_data;
}
pT = pT->m_pNext;
}
return NULL;
}

template<class T>
void CList<T>::Insert(const int &pos,const T &data)
{
if(pos <= 0 || pos >m_len)
{
cout<<"输入不合法"<<endl;
return;
}

int i = 0;
Node<T> *pT = m_pHead->m_pNext;
Node<T> *pPre = NULL;
Node<T> *pBehind = NULL;
while(pT)
{
++i;
if(i == pos - 1)
{
pPre = pT;
}
if(i == pos)
{
pBehind = pT->m_pNext;
break;
}
pT = pT->m_pNext;
}
Node<T> *pNew = new Node<T>;
pNew->m_data = data;
if(!pPre)//如果指针为空则说明pos是指第一个元素
{
pNew->m_pNext = m_pHead->m_pNext;
m_pHead->m_pNext = pNew;
++m_len;
return;
}
if(!pBehind)//如果指针为空则说明pos是指最后一个元素
{
m_pEnd->m_pNext = pNew;
}
pPre->m_pNext = pNew;
pNew->m_pNext = pT;

++m_len;

}