def test_negative(self):
     self.assertEqual(-8, findMissing([-16, -12, -4]))
 def test_positive(self):
     self.assertEqual(4, findMissing([2, 6, 8, 10, 12, 14, 16]))
 def test_mix(self):
     self.assertEqual(0, findMissing([-5, 5, 10, 15]))
 def test_negative(self):
     self.assertEqual(-8, findMissing([-16, -12, -4]))
 def test_positive(self):
     self.assertEqual(4, findMissing([2, 6, 8, 10, 12, 14, 16]))
 def test_mix(self):
     self.assertEqual(0, findMissing([-5, 5, 10, 15]))