public static LeetCode450TreeNode DeleteNode(LeetCode450TreeNode root, int key)
{
if (root == null)
{
return(null);
}
if (key > root.val)
{
root.right = DeleteNode(root.right, key);
}
else if (key < root.val)
{
root.left = DeleteNode(root.left, key);
}
else
{
if (!root.IsLeaf())
{
root = null;
}
else if (root.HasRightChild())
{
root.val = Successor(root);
root.right = DeleteNode(root.right, root.val);
}
else
{
root.val = Predecessor(root);
root.left = DeleteNode(root.left, root.val);
}
}
return(root);
}
private static int Predecessor(LeetCode450TreeNode root)
{
root = root.left;
while (root.right != null)
{
root = root.right;
}
return(root.val);
}
public LeetCode450TreeNode(int val = 0, LeetCode450TreeNode left = null, LeetCode450TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
