import unittest
# Solution
def is_first_come_first_served(xs, ys, zs):
i, j = 0, 0
for z in zs:
if i < len(xs) and z == xs[i]:
i += 1
elif j < len(ys) and z == ys[j]:
j += 1
else:
return False
return i == len(xs) and j == len(ys)
# Tests
class Test(unittest.TestCase):
def test_both_registers_have_same_number_of_orders(self):
result = is_first_come_first_served([1, 4, 5], [2, 3, 6],
[1, 2, 3, 4, 5, 6])
self.assertTrue(result)
def test_registers_have_different_lengths(self):
result = is_first_come_first_served([1, 5], [2, 3, 6], [1, 2, 6, 3, 5])
self.assertFalse(result)
def test_one_register_is_empty(self):
result = is_first_come_first_served([], [2, 3, 6], [2, 3, 6])
self.assertTrue(result)
def test_served_orders_is_missing_orders(self):
result = is_first_come_first_served([1, 5], [2, 3, 6], [1, 6, 3, 5])
self.assertFalse(result)
def test_served_orders_has_extra_orders(self):
result = is_first_come_first_served([1, 5], [2, 3, 6],
[1, 2, 3, 5, 6, 8])
self.assertFalse(result)
def test_one_register_has_extra_orders(self):
result = is_first_come_first_served([1, 9], [7, 8], [1, 7, 8])
self.assertFalse(result)
def test_one_register_has_unserved_orders(self):
result = is_first_come_first_served([55, 9], [7, 8], [1, 7, 8, 9])
self.assertFalse(result)
# Bonus
def test_handles_repeats(self):
actual = is_first_come_first_served([1, 2, 1], [3, 4, 5, 5],
[3, 4, 1, 5, 5, 2, 1])
self.assertTrue(actual)
def test_kitchen_didnt_serve(self):
actual = is_first_come_first_served([1, 2], [3, 4], [1, 3, 4])
self.assertFalse(actual)
def test_customer_didnt_pay(self):
actual = is_first_come_first_served([2], [3, 4], [1, 3, 4])
self.assertFalse(actual)
unittest.main(verbosity=2)
