Given a Binary Search Tree (BST) with the root node root
, return the minimum difference between the values of any two different nodes in the tree.
Example :
Input: root = [4,2,6,1,3,null,null] Output: 1 Explanation: Note that root is a TreeNode object, not an array. The given tree [4,2,6,1,3,null,null] is represented by the following diagram: 4 / 2 6 / \ 1 3 while the minimum difference in this tree is 1, it occurs between node 1 and node 2, also between node 3 and node 2.
Note:
- The size of the BST will be between 2 and
100
. - The BST is always valid, each node‘s value is an integer, and each node‘s value is different.
# Definition for a binary tree node. # class TreeNode(object): # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution(object): def minDiffInBST(self, root): """ :type root: TreeNode :rtype: int """ diff=100000 last_visited=None stack=[] node=root while node or stack: if node: stack.append(node) node=node.left else: node=stack.pop() if last_visited and abs(last_visited.val-node.val)<diff: diff=abs(last_visited.val-node.val) last_visited=node node=node.right return diff
原文地址:https://www.cnblogs.com/chiyeung/p/10011051.html
时间: 2024-11-10 17:56:12