# 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: def __init__(self): self.value = 0 def computeGreaterTree(self, root: TreeNode): if root is None: return self.computeGreaterTree(root.right) root.val += self.value self.value = root.val self.computeGreaterTree(root.left) def convertBST(self, root: TreeNode) -> TreeNode: self.computeGreaterTree(root) return root