public void IsProperSubsetOfTest1()
 {
     Assert.IsTrue(testSet.IsProperSubsetOf(new int[] { 15, 19, 25, 128, 1992, 54, -7, -72, 45, 89, -801, 90 }));
     Assert.IsTrue(testSet.IsProperSubsetOf(new int[] { 15, 19, 25, 128, 1992, 54, 75, 12, -7, -72 }));
 }