二叉树面试题—前，中，后序（非递归），判断是否为完全二叉树

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二叉树的基本操作

Node* GetParent(Node* x) //得到父节点    {        if ( _pRoot == NULL)            return _pRoot;        return _GetParent(_pRoot, x);    }    Node* Find(const T& value) //查找结点    {        return _FindNode(_pRoot, value);    }    size_t Hight()  //求树的高度    {        return _Hight(_pRoot);    }    size_t GetLeefNode() //求叶子节点的个数    {        return _GetLeefNode(_pRoot);    }    size_t GetLevelNode(size_t k)   //求第K层节点的个数    {        return _GetLevelNode(_pRoot,k);    }    void PreOrder_Nor()   //前序遍历(不用递归)    {        if (_pRoot)            _PreOrder_Nor(_pRoot);    }    void InOrder_Nor()   //中序遍历（不用递归）    {        if (_pRoot)            _InOrder_Nor(_pRoot);    }    void PostOrder_Nor()   //后序遍历（不用递归）    {        if (_pRoot)            _PostOrder_Nor(_pRoot);    }    void GetBinaryMirror()   //求二叉树的镜像    {        if (_pRoot)             _GetBinaryMirror(_pRoot);    }    void GetBinaryMirror_Nor()   //求二叉树的镜像（非递归）    {        if (_pRoot)            _GetBinaryMirror(_pRoot);    }    bool isCompleteBinaryTree()   //判断是否为完全二叉树    {        if (_pRoot)        {            queue<Node*> q;            q.push(_pRoot);            bool isComplete = true;            while (!q.empty())            {                Node* Front = q.front();                q.pop();                if (!isComplete && (Front->_pLeft || Front->_pRight))                {                    return false;                }                if (Front->_pLeft)                    q.push(Front->_pLeft);                if (Front->_pRight)                    q.push(Front->_pRight);                else                 {                    isComplete = false;                }            }            return true;        }        return false;    }

    Node* _GetParent(Node* proot, Node* x)    {        if (proot->_pLeft == x || proot ->_pRight == x)            return proot;         if (proot->_pLeft == NULL || proot->_pRight == NULL)            return NULL;        Node* Temp = _GetParent(proot->_pLeft, x);        if (Temp == NULL)        {            Temp = _GetParent(proot->_pRight, x);        }         return Temp;    }    Node* _FindNode(Node* proot, const T& value)    {        if ( proot == NULL || proot->_value == value)            return proot;        Node* Temp = _FindNode(proot->_pLeft,value);        if (Temp == NULL)        {            Temp = _FindNode(proot->_pRight, value);        }        return Temp;    }    size_t _Hight(Node* proot)    {        if (proot == NULL)            return 0;        size_t LeftHight = 1+_Hight(proot->_pLeft);        size_t RightHight = 1+_Hight(proot->_pRight);        return (LeftHight>RightHight)?LeftHight:RightHight;    }    size_t _GetLeefNode(Node* proot)    {        if (proot == NULL)            return 0;        if (proot->_pLeft == NULL && proot ->_pRight == NULL)            return 1;        size_t LeftLeefNode = _GetLeefNode(proot->_pLeft);        size_t RightLeefNode = _GetLeefNode(proot->_pRight);            return (LeftLeefNode+RightLeefNode);    }    size_t _GetLevelNode(Node* proot, size_t k)    {        size_t h = _Hight(proot);        if (k == 1)            return 1;        if (  proot == NULL || k> h )            return 0;        size_t LeftLevelNode  = _GetLevelNode(proot->_pLeft,k-1);        size_t RightLevelNode = _GetLevelNode(proot->_pRight,k-1);        return (LeftLevelNode+RightLevelNode);    }    void _PreOrder_Nor(Node* proot)    {        cout<<"前序：";        stack<Node*> st;        st.push(proot);        while (!st.empty())        {            Node* temp = st.top();            cout<<temp->_value<<"->";            st.pop();            if ( temp->_pRight )                st.push(temp->_pRight);            if ( temp->_pLeft )                st.push(temp->_pLeft);              }        cout<<"end"<<endl;    }    void _InOrder_Nor(Node* proot)    {        cout<<"中序：";        stack<Node*> st;        Node* temp = proot;        while ( temp || !st.empty() )        {            while (temp)            {                st.push(temp);                temp = temp->_pLeft;            }            Node* Top = st.top();            st.pop();            cout<<Top->_value<<"->";            temp = Top->_pRight;        }        cout<<"end"<<endl;    }    void _PostOrder_Nor(Node* proot)    {        cout<<"后序：";        stack<Node*> st;        Node* pCur = proot;        Node* pPre = NULL;        while ( pCur || !st.empty() )        {            while (pCur)            {                st.push(pCur);                pCur = pCur->_pLeft;            }            pCur = st.top();            if ( pCur->_pRight == NULL || pCur ->_pRight  == pPre)            {                cout<<pCur->_value<<"->";                st.pop();                pPre = pCur;                pCur = NULL;            }            else                 pCur = pCur->_pRight;        }        cout<<"end"<<endl;    }    void _GetBinaryMirror(Node* &proot)    {        if (proot == NULL)            return;        if (proot ->_pLeft  || proot->_pRight )            swap(proot->_pLeft, proot->_pRight);        _GetBinaryMirror(proot->_pLeft);        _GetBinaryMirror(proot->_pRight);    }    void _GetBinaryMirror_Nor(Node* &proot)    {        queue<Node*> q;        q.push(proot);        while(!q.empty())        {            Node* pCur = q.front();            q.pop();            std::swap(pCur->_pLeft, pCur->_pRight);            if (pCur->_pLetf)                q.push(pCur->_pLetf);            if (pCur->_pRight)                q.push(pCur->_pRight);        }    }

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