public virtual void TestCommonAncestor()
{
NUnit.Framework.Assert.AreEqual(1, graph.CommonAncestor(graph.GetNodeByIndex(43), graph.GetNodeByIndex(44)));
NUnit.Framework.Assert.AreEqual(1, graph.CommonAncestor(graph.GetNodeByIndex(41), graph.GetNodeByIndex(39)));
NUnit.Framework.Assert.AreEqual(1, graph.CommonAncestor(graph.GetNodeByIndex(39), graph.GetNodeByIndex(41)));
NUnit.Framework.Assert.AreEqual(2, graph.CommonAncestor(graph.GetNodeByIndex(40), graph.GetNodeByIndex(42)));
NUnit.Framework.Assert.AreEqual(2, graph.CommonAncestor(graph.GetNodeByIndex(42), graph.GetNodeByIndex(40)));
// too far for this method
NUnit.Framework.Assert.AreEqual(-1, graph.CommonAncestor(graph.GetNodeByIndex(10), graph.GetNodeByIndex(42)));
// assertEquals(null, common);
NUnit.Framework.Assert.AreEqual(0, graph.CommonAncestor(graph.GetNodeByIndex(10), graph.GetNodeByIndex(10)));
NUnit.Framework.Assert.AreEqual(0, graph.CommonAncestor(graph.GetNodeByIndex(40), graph.GetNodeByIndex(40)));
// assertEquals(40, common.index());
// a couple tests at the top of the graph
NUnit.Framework.Assert.AreEqual(2, graph.CommonAncestor(graph.GetNodeByIndex(10), graph.GetNodeByIndex(1)));
NUnit.Framework.Assert.AreEqual(2, graph.CommonAncestor(graph.GetNodeByIndex(1), graph.GetNodeByIndex(10)));
}