广义表的实现

广义表：广义表(Lists，又称列表)是一种非线性的数据结构，是线性表的一种推广。即广义表中放松对表元素的原子限制，容许它们具有其自身结构。

毫无疑问，广义表是一种线性表的推广，也有人叫做列表。

• 广义表存储结构

  广义表中的元素是可以具有不同结构的，所以难以用顺序结构来表示，通常都采用链式的存储结构。在这个结构中我们共有三种类型的节点，一种保存正常值的，一种是头节点，一种是子表节点。
  在这里我们来看看下面几种的存储结构。
  A = ()
  B = (a,b,c)
  C = (a,b,(c,d),e)
  D = (a,b,(c,d),(e,(f),h))

这就是广义表的结构，具体的结构，请参考我下方的设计。

• 广义表的实现

#define _CRT_SECURE_NO_WARNINGS 1#include<iostream>#include<cstdlib>#include<cassert>using namespace std;enum type{    HEAD,    VALUE,    SUB};struct GeneralizedNode{    GeneralizedNode(const type & type,const char &value=0)    :_type(type)    ,_next(NULL)    , _sublink(NULL)    {        _value=value;    }    type _type;    GeneralizedNode *_next;    union    {        char _value;        GeneralizedNode *_sublink;    };};class Generalized{public:    Generalized()        :_head(NULL)    {}    Generalized(const char *str)        :_head(NULL)    {        _head = _Createlist(str);    }    Generalized(const Generalized& g)    {        _head=_Copyconstruction(g._head);    }    //传统写法    Generalized& operator =(const Generalized &d)    {        if (this != &d)        {            GeneralizedNode* tmp = _Copyconstruction(d._head);            _Destroy(_head);            _head = tmp;        }            return *this;    }    //现代写法    /*Generalized& operator =(const Generalized &d)    {        if (this != &d)        {            Generalized tmp(d);            swap(_head, tmp._head);        }        return *this;    }*/    ~Generalized()    {        if (_head)        {            _Release(_head);        }    }    void print()    {        if (_head)        {            _print(_head);        }        cout << endl;    }    size_t size()    {        if (_head)        {            return _size(_head);        }        else        {            return 0;        }    }    size_t Depth()    {        if (_head)        {            return _Depth(_head);        }        else        {            return 0;        }    }protected:    GeneralizedNode* _assignment(GeneralizedNode *head)    {        assert(head);        GeneralizedNode *newlist = new GeneralizedNode(HEAD);        GeneralizedNode *cur = head->_next;        GeneralizedNode *newcur = newlist;        while (cur)        {            if (cur->_type == SUB)            {                GeneralizedNode *subnode = new GeneralizedNode(SUB);                subnode->_sublink = _assignment(cur->_sublink);                newcur->_next = subnode;                newcur = subnode;                cur = cur->_next;            }            else            {                GeneralizedNode *newnode = new GeneralizedNode(cur->_type, cur->_value);                newcur->_next = newnode;                newcur = newnode;                cur = cur->_next;            }        }        return newlist;    }    GeneralizedNode* _Copyconstruction(GeneralizedNode *head)    {        assert(head);        GeneralizedNode *newlist = new GeneralizedNode(HEAD);        GeneralizedNode *cur = head->_next;        GeneralizedNode *newcur = newlist;        while (cur)        {            if (cur->_type == SUB)            {                GeneralizedNode* newnode = new GeneralizedNode(cur->_type);                newnode->_sublink = _Copyconstruction(cur->_sublink);                newcur->_next = newnode;                newcur = newnode;                cur = cur->_next;            }            else            {                GeneralizedNode* newnode = new GeneralizedNode(cur->_type, cur->_value);                newcur->_next = newnode;                newcur = newcur->_next;                cur = cur->_next;            }        }        return newlist;    }    void _Release(GeneralizedNode *head)    {        assert(head);        GeneralizedNode* cur = head;        while (cur)        {            if (cur->_type == SUB)            {                _Release(cur->_sublink);            }            GeneralizedNode *del = cur;            cur = cur->_next;            delete del;            del = NULL;        }    }    size_t _Depth(GeneralizedNode *head)    {        assert(head);        GeneralizedNode *cur = head;        size_t maxdep = 1;        while (cur)        {            if (cur->_type == SUB)            {                size_t dep = 1;                dep+=_Depth(cur->_sublink);                if (dep > maxdep)                {                    maxdep = dep;                }            }                cur = cur->_next;        }        return maxdep;    }    size_t _size(GeneralizedNode *head)    {        assert(head);        GeneralizedNode* cur = head;        size_t count = 0;        while (cur)        {            if (cur->_type == VALUE)            {                count++;                cur = cur->_next;            }            else if(cur->_type==SUB)            {                count += _size(cur->_sublink);                cur = cur->_next;            }            else            {                cur = cur->_next;            }        }        return count;    }    void _print(GeneralizedNode *& head)    {        assert(head);        GeneralizedNode *cur = head;        cout << '(';        while (cur)        {            if (cur->_type == VALUE)            {                cout << cur->_value;                if (cur->_next != NULL)                {                    cout << ',';                }                cur = cur->_next;            }            else if (cur->_type == HEAD)            {                cur = cur->_next;            }            else if (cur->_type==SUB)            {                _print(cur->_sublink);                if (cur->_next != NULL)                {                    cout << ',';                }                cur = cur->_next;            }        }        cout << ')';    }    GeneralizedNode* _Createlist(const char *&str)    {        assert(str);        GeneralizedNode *head = new GeneralizedNode(HEAD);        GeneralizedNode *cur = head;        str++;        while (*str)        {            if ((*str >= '0'&&*str <= '9') || (*str >= 'a'&&*str <= 'z') || (*str >= 'A'&&*str <= 'Z'))            {                GeneralizedNode* node = new GeneralizedNode(VALUE,*str);                cur->_next = node;                cur = cur->_next;                str++;            }            else if (*str=='(')            {                GeneralizedNode* node = new GeneralizedNode(SUB);                cur->_next = node;                cur = cur->_next;                cur->_sublink = _Createlist(str);            }            else if (*str == ')')            {                cur->_next = NULL;                str++;                return head;            }            else            {                str++;            }        }        return head;    }protected:    GeneralizedNode* _head;};void test1(){    Generalized g1("(a,b,(a,b),c,(d,((),()),a))");    Generalized g3("(((), ()))");    Generalized g2(g3);    Generalized g4 = g1;    cout<<g1.Depth() << endl;    g4.print();    /*cout<<g2.Depth() << endl;    cout << g2.size() << endl;    g2.print();    g1 = g1;*///  Generalized g4(g3);    //g3.print();    /*g1.print();    cout << g1.Depth() << endl;    cout << g3.Depth() << endl;*/    //g4.print();    cout << g1.size() << endl;    //cout << g3.size() << endl;    //cout << g4.size() << endl;}int main(){    test1();    system("pause");    return 0;}