数据结构-二叉树编程

求二叉树叶子数量

如果节点的左子树与右子树相同且为NULL

int num=0;
void GetLeavesNum(BN* a)
{
    if (a == NULL)
        return;
    if (a->lchild == NULL && a->rchild == NULL)
    {
        num++;
    }
    GetLeavesNum(a->lchild);
    GetLeavesNum(a->rchild);
}
​

求二叉树的高度

左子树和右子树取最大值再加一就是这棵树的高度

int GetTreeHeight(BN* a)
{
    if (a == NULL)
        return 0;
​
    //获取左子树高度
    int lHeight = GetTreeHeight(a->lchild);
    //获取右子树高度
    int rHeight = GetTreeHeight(a->rchild);
    if (lHeight > rHeight)
    {
        return lHeight + 1;
    }
    else if(rHeight>lHeight)
    {
        return rHeight + 1;
    }
    else
    {
        return lHeight+1;
    }
}

拷贝二叉树

BN* CopyBinaryTree(BN* a)
{
    if (a == NULL)
    {
        return NULL;
    }
    //BN*test =  (BN*)malloc(sizeof(BN));
    //test->ch = a->ch;
    //test->lchild = a->lchild;
    //test->rchild = a->rchild;
    BN*lchild = CopyBinaryTree(a->lchild);
    BN*rchild = CopyBinaryTree(a->rchild);
    BN* test = (BN*)malloc(sizeof(BN));
    test->ch = a->ch;
    test->lchild = lchild;
    test->rchild = rchild;
    return test;
}

释放二叉树

void DeleteBinaryTree(BN* a)
{
    if (a == NULL)
    {
        return;
    }
    //先删除左
    DeleteBinaryTree(a->lchild);
    //再删除右
    DeleteBinaryTree(a->rchild);
    delete(a);
    a = NULL;
}