算法（7） —— 统计树的特定点

1. 统计节点数

int CountNodes ( SearchTree T )     {
    if ( T == NULL)
        return 0;
    else 
        return 1 + CountNodes ( T->Left) + CountNodes (T->Right);
}

2.统计叶子树

int CountLeaves (SearchTree T)      {
    if  (T == NULL)
        return 0;
    else if (T->Left == NULL && T->Right == NULL)
        return 1;
    else return CountLeaves (T->Right) + CountLeaves (T -> Left);
}

3.统计左右孩子都存在的双亲节点数

int CountFull  (SearchTree T)    {
    if ( T == NULL)   
        return 0;
    else return (T->Right != NULL && T->Left != NULL) +
                 CountFull (T->Left) + CountFull (T->Right);
}

以上函数已经更新到 tree.h 中。