public void Test05_SortedDictionary()
{
SortedDictionary <DateTime, decimal> testSortedDict = new SortedDictionary <DateTime, decimal>();
DateTime key1 = DateTime.Today;
DateTime key2 = DateTime.Today.AddMonths(-7);
DateTime key3 = new DateTime(2020, 1, 1, 13, 2, 3);
testSortedDict.Add(key1, 1000);
testSortedDict.Add(key2, 767);
testSortedDict.Add(key3, -6143);
Assert.AreEqual(false, testSortedDict.AddIfNotContains(key3, 121));
Assert.AreEqual(3, testSortedDict.Count);
}