public void TesBalancedTree()
{
var root = new TreeNode(3);
root.Left = new TreeNode(9);
root.Right = new TreeNode(20);
root.Right.Left = new TreeNode(15);
root.Right.Right = new TreeNode(7);
var r = BalancedTree.IsBalanced(root);
Assert.AreEqual(r, true);
root = new TreeNode(1);
root.Left = new TreeNode(2);
root.Right = new TreeNode(2);
root.Left.Left = new TreeNode(3);
root.Left.Right = new TreeNode(3);
root.Left.Left.Left = new TreeNode(4);
root.Left.Left.Right = new TreeNode(4);
r = BalancedTree.IsBalanced(root);
Assert.AreEqual(r, false);
}