def test_4321(self):
seq = [4, 3, 2, 1]
self.assertEqual(answer4_2(seq), '1')
def test_1324(self):
seq = [1, 3, 2, 4]
self.assertEqual(answer4_2(seq), '2')
def test_3214(self):
seq = [3, 2, 1, 4]
self.assertEqual(answer4_2(seq), '3')
def test_421356(self):
seq = [4, 2, 1, 3, 5, 6]
self.assertEqual(answer4_2(seq), '20')
def test_12345678910(self):
seq = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
self.assertEqual(answer4_2(seq), '1')
def test_52981(self):
seq = [5, 2, 9, 8, 1]
self.assertEqual(answer4_2(seq), '6')
def test_59821(self):
seq = [5, 9, 8, 2, 1]
self.assertEqual(answer4_2(seq), '6')
