IEnumerable <int> TraversePostOrder(TraverseNode root)
{
if (root.Left != null)
{
foreach (var value in TraversePostOrder(root.Left).ToList())
{
yield return(value);
}
}
if (root.Right != null)
{
foreach (var value in TraversePostOrder(root.Right).ToList())
{
yield return(value);
}
}
yield return(root.Value);
}
void TestPostOrderTraversal(TraverseNode root, int[] expected)
{
var actual = TraversePostOrder(root).ToList();
Assert.True(expected.SequenceEqual(actual));
}