public void TestRemoveItem()
 {
     smallDistribution.RemoveItem("item1");
     smallDistribution.RemoveItem("item2");
     smallDistribution.RemoveItem("item3");
     Assert.AreEqual(2, smallDistribution.GetCount("item1"));
     Assert.AreEqual(1, smallDistribution.GetCount("item2"));
     smallDistribution.AddItem("item1");
     smallDistribution.AddItem("item2");
     smallDistribution.AddItem("item3");
 }