python/exercises/practice/alphametics/alphametics_test.py

# These tests are auto-generated with test data from:
# https://github.com/exercism/problem-specifications/tree/main/exercises/alphametics/canonical-data.json
# File last updated on 2023-07-20

import unittest

from alphametics import (
    solve,
)


class AlphameticsTest(unittest.TestCase):
    def test_puzzle_with_three_letters(self):
        self.assertEqual(solve("I + BB == ILL"), {"I": 1, "B": 9, "L": 0})

    def test_solution_must_have_unique_value_for_each_letter(self):
        self.assertEqual(solve("A == B"), None)

    def test_leading_zero_solution_is_invalid(self):
        self.assertEqual(solve("ACA + DD == BD"), None)

    def test_puzzle_with_two_digits_final_carry(self):
        self.assertEqual(
            solve("A + A + A + A + A + A + A + A + A + A + A + B == BCC"),
            {"A": 9, "B": 1, "C": 0},
        )

    def test_puzzle_with_four_letters(self):
        self.assertEqual(solve("AS + A == MOM"), {"A": 9, "S": 2, "M": 1, "O": 0})

    def test_puzzle_with_six_letters(self):
        self.assertEqual(
            solve("NO + NO + TOO == LATE"),
            {"N": 7, "O": 4, "T": 9, "L": 1, "A": 0, "E": 2},
        )

    def test_puzzle_with_seven_letters(self):
        self.assertEqual(
            solve("HE + SEES + THE == LIGHT"),
            {"E": 4, "G": 2, "H": 5, "I": 0, "L": 1, "S": 9, "T": 7},
        )

    def test_puzzle_with_eight_letters(self):
        self.assertEqual(
            solve("SEND + MORE == MONEY"),
            {"S": 9, "E": 5, "N": 6, "D": 7, "M": 1, "O": 0, "R": 8, "Y": 2},
        )

    def test_puzzle_with_ten_letters(self):
        self.assertEqual(
            solve("AND + A + STRONG + OFFENSE + AS + A + GOOD == DEFENSE"),
            {
                "A": 5,
                "D": 3,
                "E": 4,
                "F": 7,
                "G": 8,
                "N": 0,
                "O": 2,
                "R": 1,
                "S": 6,
                "T": 9,
            },
        )

    # See https://github.com/exercism/python/pull/1358
    @unittest.skip("extra-credit")
    def test_puzzle_with_ten_letters_and_199_addends(self):
        """This test may take a long time to run. Please be patient when running it."""
        puzzle = (
            "THIS + A + FIRE + THEREFORE + FOR + ALL + HISTORIES + I + TELL"
            "+ A + TALE + THAT + FALSIFIES + ITS + TITLE + TIS + A + LIE +"
            "THE + TALE + OF + THE + LAST + FIRE + HORSES + LATE + AFTER +"
            "THE + FIRST + FATHERS + FORESEE + THE + HORRORS + THE + LAST +"
            "FREE + TROLL + TERRIFIES + THE + HORSES + OF + FIRE + THE +"
            "TROLL + RESTS + AT + THE + HOLE + OF + LOSSES + IT + IS +"
            "THERE + THAT + SHE + STORES + ROLES + OF + LEATHERS + AFTER +"
            "SHE + SATISFIES + HER + HATE + OFF + THOSE + FEARS + A + TASTE"
            "+ RISES + AS + SHE + HEARS + THE + LEAST + FAR + HORSE + THOSE"
            "+ FAST + HORSES + THAT + FIRST + HEAR + THE + TROLL + FLEE +"
            "OFF + TO + THE + FOREST + THE + HORSES + THAT + ALERTS + RAISE"
            "+ THE + STARES + OF + THE + OTHERS + AS + THE + TROLL +"
            "ASSAILS + AT + THE + TOTAL + SHIFT + HER + TEETH + TEAR + HOOF"
            "+ OFF + TORSO + AS + THE + LAST + HORSE + FORFEITS + ITS +"
            "LIFE + THE + FIRST + FATHERS + HEAR + OF + THE + HORRORS +"
            "THEIR + FEARS + THAT + THE + FIRES + FOR + THEIR + FEASTS +"
            "ARREST + AS + THE + FIRST + FATHERS + RESETTLE + THE + LAST +"
            "OF + THE + FIRE + HORSES + THE + LAST + TROLL + HARASSES + THE"
            "+ FOREST + HEART + FREE + AT + LAST + OF + THE + LAST + TROLL"
            "+ ALL + OFFER + THEIR + FIRE + HEAT + TO + THE + ASSISTERS +"
            "FAR + OFF + THE + TROLL + FASTS + ITS + LIFE + SHORTER + AS +"
            "STARS + RISE + THE + HORSES + REST + SAFE + AFTER + ALL +"
            "SHARE + HOT + FISH + AS + THEIR + AFFILIATES + TAILOR + A +"
            "ROOFS + FOR + THEIR + SAFE == FORTRESSES"
        )
        self.assertEqual(
            solve(puzzle),
            {
                "A": 1,
                "E": 0,
                "F": 5,
                "H": 8,
                "I": 7,
                "L": 2,
                "O": 6,
                "R": 3,
                "S": 4,
                "T": 9,
            },
        )