66c38f8656
Write a predicate that tests if a given list of integers, zs, is a possible interleaving of two other lists, xs and ys.
64 lines
2.1 KiB
Python
64 lines
2.1 KiB
Python
import unittest
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# Solution
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def is_first_come_first_served(xs, ys, zs):
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i, j = 0, 0
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for z in zs:
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if i < len(xs) and z == xs[i]:
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i += 1
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elif j < len(ys) and z == ys[j]:
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j += 1
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else:
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return False
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return i == len(xs) and j == len(ys)
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# Tests
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class Test(unittest.TestCase):
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def test_both_registers_have_same_number_of_orders(self):
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result = is_first_come_first_served([1, 4, 5], [2, 3, 6],
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[1, 2, 3, 4, 5, 6])
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self.assertTrue(result)
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def test_registers_have_different_lengths(self):
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result = is_first_come_first_served([1, 5], [2, 3, 6], [1, 2, 6, 3, 5])
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self.assertFalse(result)
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def test_one_register_is_empty(self):
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result = is_first_come_first_served([], [2, 3, 6], [2, 3, 6])
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self.assertTrue(result)
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def test_served_orders_is_missing_orders(self):
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result = is_first_come_first_served([1, 5], [2, 3, 6], [1, 6, 3, 5])
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self.assertFalse(result)
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def test_served_orders_has_extra_orders(self):
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result = is_first_come_first_served([1, 5], [2, 3, 6],
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[1, 2, 3, 5, 6, 8])
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self.assertFalse(result)
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def test_one_register_has_extra_orders(self):
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result = is_first_come_first_served([1, 9], [7, 8], [1, 7, 8])
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self.assertFalse(result)
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def test_one_register_has_unserved_orders(self):
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result = is_first_come_first_served([55, 9], [7, 8], [1, 7, 8, 9])
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self.assertFalse(result)
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# Bonus
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def test_handles_repeats(self):
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actual = is_first_come_first_served([1, 2, 1], [3, 4, 5, 5],
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[3, 4, 1, 5, 5, 2, 1])
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self.assertTrue(actual)
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def test_kitchen_didnt_serve(self):
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actual = is_first_come_first_served([1, 2], [3, 4], [1, 3, 4])
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self.assertFalse(actual)
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def test_customer_didnt_pay(self):
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actual = is_first_come_first_served([2], [3, 4], [1, 3, 4])
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self.assertFalse(actual)
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unittest.main(verbosity=2)
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