寻找二叉查找树中比指定值小的所有节点中最大的那个节点

最新推荐文章于 2023-11-03 19:02:08 发布

weixin_30745641

最新推荐文章于 2023-11-03 19:02:08 发布

阅读量498

点赞数

CC 4.0 BY-SA版权

文章标签： python

原文链接：http://www.cnblogs.com/xiayy860612/archive/2012/10/16/2726861.html

本文介绍了一种在二叉搜索树中寻找小于给定值的最大节点的方法。通过遍历树结构，该算法能够找到最接近目标值的节点，适用于多种编程应用场景。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

There is a binary search tree, now I want to look for a node its value is the max of the nodes which are lower than the number which I passed.

For example:

1 2 3 4 7 9

If I give 4, it need get the node 3.

If I give 6, it need get the node 4.

struct ListNode
{
    int data;
    ListNode *par;
    ListNode *left;
    ListNode *right;
};


ListNode* GetMaxNumInLowerNums2(ListNode* cur,int num)
{
    ListNode *max = NULL;
    //search tree and record the expected node by max
    /*
    if the node which values num is not exist,
        the expected node is the nearest parent node of num which has right child tree.
　　or exist, the expected node is the greatest node in its left child tree.
    1.  greater to num, it means the position of num is in the right child tree of current node 
        and record current node.
    2.  lower to num, it means the position of num is in the left child tree of current node.
    3.  equal to num, it means the expected node is in the left child tree 
        and that node is the greatest one in left child tree.
    */
    while(cur != NULL)
    {
        if(cur->data < num)
        {
            max = cur;
            cur = cur->right;
        }
        else cur = cur->left;
    }
    return max;
}