[리트코드 leetcode] 783. Minimum Distance Between BST Nodes

leetcode.com/problems/minimum-distance-between-bst-nodes/submissions/

Minimum Distance Between BST Nodes - LeetCode

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
    diff = sys.maxsize
    prev = sys.maxsize
    def minDiffInBST(self, root: TreeNode) -> int:
        
        def recur(node):
            if not node:
                return 
            
            recur(node.right)
            
            self.diff = min(self.diff, self.prev - node.val)
            self.prev = node.val
            
            recur(node.left)
            
            return node
        
        recur(root)
        return self.diff