private static void Helper(LeetCode530TreeNode root)
{
if (root == null)
{
return;
}
Helper(root.left);
if (pre != int.MinValue)
{
ans = Math.Min(ans, root.val - pre);
}
pre = root.val;
Helper(root.right);
}
public LeetCode530TreeNode(int val = 0, LeetCode530TreeNode left = null, LeetCode530TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
public static int GetMinimumDifference(LeetCode530TreeNode root)
{
Helper(root);
return(ans);
}