C二叉樹求節點個數和葉子節點個數（遞歸形式）

struct BiTree
{
    struct BiTree *lchild;
    struct BiTree *rchild;
};

int Node(struct BiTree *T)
{
    if(T == NULL)
        return 0;
    return 1+Node(T->lchild)+Node(T->rchild);
}

int Leaf(struct BiTree *T)
{
    if(T==NULL)
        return 0;
    if(T->lchild == NULL && T->rchild == NULL)
        return 1;
    return Leaf(T->lchild)+Leaf(T->rchild);
}