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【C++】c++實現線性表、連結串列

c++實現動態順序表如下

typedef int DataType;
class SeqList
{
public: 
    //////////////類的基本成員函式定義/////////////////
    SeqList()                     //建構函式(在類內定義)
        :_elem(NULL)
        , _capacity(0)
        , _size(0)
    {}
    ~SeqList()                  //解構函式
    {
        if (_elem)
        {
            delete[] _elem;
            cout << "~SeqList()"
<< endl; } } SeqList(const SeqList& s) //拷貝建構函式 :_elem(new DataType[s._capacity]) , _capacity(s._capacity) , _size(s._size) { memcpy(_elem, s._elem, _size*sizeof(DataType)); } SeqList& operator= (const SeqList& s) //賦值操作符過載
{ if (this != &s) //防止自賦值 { delete[] _elem;//釋放原來空間 _elem = new DataType[s._capacity];//分配新空間 memcpy(_elem, s._elem, s._size*sizeof(DataType)); _size = s._size; _capacity = s._capacity; } return *this; } ///
///////動態順序表的基本操作實現///////////////
void _CheckCapacity(); //在類外定義 void _PrintSeqList(); void _PushBack(DataType data); void _PopBack(); size_t Find(DataType data); void Insert(size_t index,DataType data); private: DataType* _elem; //指向當前空間的指標 size_t _capacity; //當前空間容量大小 size_t _size; //但錢空間有效資料的個數 };

類外定義成員函式如下:

void SeqList::_CheckCapacity()         //檢查容量
{
    if (_size == _capacity)
    {
        _capacity = _capacity * 2 + 5;//建構函式初始化時,_capacity為0
        DataType* ret = (DataType*)malloc(_capacity*sizeof(DataType));
        memcpy(ret, _elem, _size*sizeof(DataType));
        delete[] _elem;
        _elem = ret;
    }
}
void SeqList::_PrintSeqList()
{
    cout << "SeqList : ";
    size_t index = 0;
    for (; index < _size; index++)
    {
        cout << _elem[index] << " ";
    }
    cout << "NULL" << endl;
}
void SeqList::_PushBack(DataType data) //尾插資料
{
    _CheckCapacity();
    _elem[_size++] = data;
}
void SeqList::_PopBack()
{
    if (_size == 0)
    {
        cout << "SeqList Is Empty" << endl;
        return;
    }
    _size--;
}
size_t SeqList::Find(DataType data)    //查詢資料,返回下標
{
    size_t index = 0;
    for (; index < _size; index++)
    {
        if (_elem[index] == data)
        {
            return index;
        }
    }
    return _size+1;
}
void SeqList::Insert(size_t index, DataType data) //在下標index處插入一個數據
{
    _CheckCapacity();
    if (index > _size)
    {
        cout << "Invaid index" << endl;
        return;
    }
    int i = _size-1;
    for (; i >=(int)index; i--)  //注意此處i不能定義為size_t,且index要強轉成int型,否則會成死迴圈
    {                            //即使i一直減,但是無符號整型永遠不會小於0,
        _elem[i+1] = _elem[i];
    }
    _elem[index] = data;
    _size++;
}

基本成員函式(如構造、拷貝構造、賦值操作符過載函式)還可以優化如下:

class SeqList
{
public:
    //////////////類的基本成員函式定義/////////////////
    SeqList(DataType* elem, size_t capacity, size_t size)   //建構函式
    {
        if (elem == NULL)
        {
            _elem = NULL;
            _capacity = 0;
            _size = 0;
        }
        else
        {
            _elem = new DataType[capacity];
            memcpy(_elem, elem, size*sizeof(DataType));
            _capacity = capacity;
            _size = size;
        }
    }
    ~SeqList()                  //解構函式
    {
        if (_elem)
        {
            delete[] _elem;
            cout << "~SeqList()" << endl;
        }
    }
    void Swap(SeqList& s)
    {
        swap(_elem, s._elem);//自動呼叫系統實現的swap函式
        swap(_capacity, s._capacity);
        swap(_size, s._size);
    }
    SeqList(const SeqList& s)    //拷貝建構函式
        :_elem(NULL)
        , _capacity(0)
        , _size(0)
    {
        SeqList tmp(s._elem, s._capacity, s._size);//通過建構函式進行初始化
        Swap(tmp);  //將tmp與this的值交換,交換後this會指向原來tmp指向的空間
    }
    SeqList& operator= (const SeqList& s)  //賦值操作符過載
    {
        if (this != &s)  //防止自賦值
        {
            SeqList tmp(s._elem, s._capacity, s._size);
            Swap(tmp);
        }
        return *this;
    }
private:
    DataType* _elem;   //指向當前空間的指標
    size_t _capacity;     //當前空間容量大小
    size_t _size;          //但錢空間有效資料的個數
};

解析:

SeqList tmp(s._elem, s._capacity, s._size);
Swap(tmp);
若已經存在的兩個物件s1、s2;執行 s1 = s2 操作,則先建立一個臨時物件tmp,將s2的值拷貝給tmp,再將tmp和s1的值進行交換,最後出了作用域就會釋放這個臨時物件tmp。如下圖:

這裡寫圖片描述

c++實現連結串列如下

單向迴圈連結串列

先了解:

關鍵字struct和class是同一等級的,

唯一區別是struct定義的成員預設是公有的,而class預設的成員是私有的

typedef int DataType;
struct LinkNode
{
    LinkNode* _next;     //指向下一個節點的指標
    DataType _data;  //當前節點的資料
    LinkNode(const DataType data)    //建構函式
        :_next(NULL)
        ,_data(data)
    {}
};
class sList
{
public:
    sList()                        //建構函式
        :_head(NULL)
        ,_tail(NULL)
    {}
    sList(const sList& s)         //拷貝建構函式
        :_head(NULL)
        ,_tail(NULL)
    {
        if(s._head == NULL)
        {
            return;
        }
        LinkNode* begin = s._head;
        do
        {
            PushBack(begin->_data);  //this->PushBack(begin->_data);
            begin = begin->_next;
        } while (begin != s._head);
    }
    sList& operator= (const sList& s)   //賦值操作符過載
    {
        if (this != &s)
        {
            DistorysList();//先摧毀this指向的連結串列
            LinkNode* begin = s._head;
            do
            {
                PushBack(begin->_data);
                begin = begin->_next;
            } while (begin != s._head);
        }
        return *this;
    } 
    ~sList()                       //解構函式
    {
        Distory();
    }
    void DistorysList()            //撤銷連結串列
    {
        while (_head)
        {
            PopBack();
        }
    }
    void PushBack(DataType data)    //尾插
    {
        if (_head == NULL)
        {
            _head = new LinkNode(data);
            _tail = _head;   //迴圈連結串列
        }
        else
        {
            _tail->_next = new LinkNode(data);
            _tail = _tail->_next;
            _tail->_next = _head;
        }
    }
    void PopBack()                  //尾刪
    {
        if (_head == NULL)//空連結串列
        {
            return;
        }
        if (_head == _tail)//一個節點
        {
            delete _head;
            _head = NULL;
            _tail = NULL;
        }
        else               //多個節點
        {
            LinkNode* prev = _head;
            while (prev->_next != _tail)
            {
                prev = prev->_next;
            }
            delete _tail;
            _tail = prev;
            _tail->_next = _head;
        }
    }
    void PrintsList()                  //列印連結串列
    {
        cout << "sList->";
        if (_head != NULL)
        {
            LinkNode* begin = _head;
            do
            {
                cout << begin->_data << "->";
                begin = begin->_next;
            }while (begin != _head);
        }
        cout << "NULL" << endl;
    }
    void Reverse()               //逆置連結串列
    {
        if (_head == NULL || _head == _tail)
        {
            return;
        }
        LinkNode* begin = _head->_next;
        _head->_next = NULL;//摘下頭節點
        _tail->_next = NULL;//解開迴圈
        _tail = _head;      //原來的頭節點逆置後是尾節點
        while (begin)
        {
            LinkNode* ret = begin;
            begin = begin->_next;
            ret->_next = _head;
            _head = ret;
        }
        _tail->_next = _head;
    }
private: 
    LinkNode* _head;   //指向頭節點的指標
    LinkNode* _tail;   //指向尾節點的指標
};

雙向迴圈連結串列

typedef int DataType;
class DoubleNode
{
    friend class DoubleList;        //友元函式
public: 
    DoubleNode(DataType data)       //建構函式
        :_prev(NULL)
        , _next(NULL)
        , _data(data)
    {}
private:
    DoubleNode* _prev;
    DoubleNode* _next;
    DataType _data;
};
class DoubleList
{
public:
    DoubleList()               //建構函式
        :_head(NULL)
        , _tail(NULL)
    {}
    DoubleList(const DoubleList& d) //拷貝建構函式
        :_head(NULL)
        , _tail(NULL)
    {
        if (d._head == NULL)
        {
            return;
        }
        DoubleNode* begin = d._head;
        do
        {
            PushBack(begin->_data);
            begin = begin->_next;
        }while (begin != d._head);
    }
    DoubleList& operator= (const DoubleList& d)    //賦值操作符過載
    {
        if (this != &d)
        {
            Distory();
            DoubleNode* begin = d._head;
            do
            {
                PushBack(begin->_data);
                begin = begin->_next;
            } while (begin != d._head);
        }
        return *this;
    }
    ~DoubleList()                       //解構函式
    {
        Distory();
    }
    void Distory()                   //摧毀連結串列
    {
        while (_head)
        {
            PopFront();
        }
    }
    void PushBack(DataType data)     //尾插
    {
        if (_head == NULL)
        {
            _head = new DoubleNode(data);
            _tail = _head;
        }
        else
        {
            DoubleNode* ret = new DoubleNode(data);
            _tail->_next = ret;
            ret->_prev = _tail;
            _tail = ret;
            _tail->_next = _head;   //成環
        }
    }
    void PopFront()              //頭刪
    {
        if (_head == NULL)
        {
            cout << "DoubleList Is Empty" << endl;
        }
        else if (_head == _tail)
        {
            delete _head;
            _head = NULL;
            _tail = NULL;
        }
        else
        {
            DoubleNode* del = _head;
            _head = _head->_next;
            _head->_prev = NULL;
            _tail->_next = _head;//更新尾指標
            del->_next = NULL;
            delete del;
        }
    }
    void PrintDList()
    {
        cout << "DoubleList->";
        if (_head != NULL)
        {
            DoubleNode* begin = _head;
            do
            {
                cout << begin->_data << "->";
                begin = begin->_next;
            } while (begin != _head);
        }
        cout << "NULL" << endl;
    }
private:
    DoubleNode* _head;    //指向尾節點的指標
    DoubleNode* _tail;    //指向頭節點的指標
};