private static int PostOrder(LeetCode563TreeNode root)
{
if (root == null)
{
return(0);
}
int left = PostOrder(root.left);
int right = PostOrder(root.right);
ans += Math.Abs(left - right);
return(root.val + left + right);
}
public LeetCode563TreeNode(int val = 0, LeetCode563TreeNode left = null, LeetCode563TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
public static int TiltSumInBST(LeetCode563TreeNode root)
{
PostOrder(root);
return(ans);
}