public void CountTest()
{
var dict = new LRUCacheDictionary<string, string>();
Assert.Equal(0, dict.Count);
dict.Add("key1", "value1");
Assert.Equal(1, dict.Count);
dict.Add("key2", "value2");
Assert.Equal(2, dict.Count);
dict.Remove("key1");
Assert.Equal(1, dict.Count);
dict.Clear();
Assert.Equal(0, dict.Count);
}