public void Test_Width_Traverse()
{
var tree = new BinaryTree<int> { 90, 50, 150, 20, 75, 95, 175, 5, 25, 66, 80, 92, 111, 166, 200 };
var data = new StringBuilder();
tree.Traverse(node => data.Append(node + ", "), "Width");
Assert.AreEqual("90, 50, 150, 20, 75, 95, 175, 5, 25, 66, 80, 92, 111, 166, 200, ", data.ToString());
}