public void TryGetValueTest()
{
GraphCompositeBuilder<int, string> gcb = new GraphCompositeBuilder<int, string>(EqualityComparer<int>.Default, 0, "root");
gcb.AddNode(0, 1, "subG", true);
string value = null;
Assert.AreEqual(gcb.TryGetValue(0, out value), true);
Assert.AreEqual(value, "root");
Assert.AreEqual(gcb.TryGetValue(1, out value), true);
Assert.AreEqual(value, "subG");
value = null;
Assert.AreEqual(gcb.TryGetValue(2, out value), false);
Assert.IsNull(value);
}