A-C++ 二叉树代码

    typedef char ElemType;
    typedef struct BtNode//BinaryTreeNode
    {
    ElemType data;
    struct BtNode* leftchild;
    struct BtNode* rightchild;
    }BtNode,*BinaryTree;
    struct StkNode
    {
    BtNode* pnode;
    int pos;
    public:
    StkNode(BtNode* p) :pnode(p), pos(0) {}
    };
    BtNode* Buynode()
    {
    BtNode* s = (BtNode*)malloc(sizeof(BtNode));
    if (NULL == s)exit(1);
    memset(s, 0, sizeof(BtNode));
    return s;
    }
    //中序遍历
    void InOrder(BtNode* p)
    {
    if (p != NULL)
    {
        InOrder(p->leftchild);
        cout << p->data << " ";