public static bool IsUnivalTree(LeetCode965TreeNode root)
{
// pre-order traversal
var left = root.left == null || (root.val == root.left.val && IsUnivalTree(root.left));
// pre-order traversal
var right = root.right == null || (root.val == root.right.val && IsUnivalTree(root.right));
return(left && right);
}
public LeetCode965TreeNode(int val = 0, LeetCode965TreeNode left = null, LeetCode965TreeNode right = null)
{
this.val = val;
this.left = left;
this.right = right;
}
