2023.02.17 Today's Challenge

https://leetcode.com/problems/minimum-distance-between-bst-nodes/

Minimum Distance Between BST Nodes - LeetCode

최소값을 클래스 변수로 놓고 트리 순회하면서 구하면 됨

Class Solution:
    def __init__(self):
        self.prev = None
        self.min = float('inf')

    def minDiffInBST(self, root: Optional[TreeNode]) -> int:
        self.inOrder(root)
        return self.min

    def inOrder(self, root: TreeNode) -> None:
        if not root:
            return
        self.inOrder(root.left)

        if self.prev:
            self.min = min(self.min, root.val - self.prev.val)
        self.prev = root
        self.inOrder(root.right)