530.-minimum-absolute-difference-in-bst.md

530. Minimum Absolute Difference in BST

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution:
    def getMinimumDifference(self, root: TreeNode) -> int:
        ans =  float("inf")
        curr = None
        prev = -float("inf")
        stack = []
        while stack or root:
            while root:
                stack.append(root)
                root = root.left

            root = stack.pop()
            curr = root.val
            # print(curr)
            ans = min(ans, curr - prev)
            root = root.right
            prev = curr

        return ans