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artemkorsakov's solution

to Beer Song in the Java Track

Published at Feb 05 2019 · 0 comments
Instructions
Test suite
Solution

Recite the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.

Note that not all verses are identical.

99 bottles of beer on the wall, 99 bottles of beer.
Take one down and pass it around, 98 bottles of beer on the wall.

98 bottles of beer on the wall, 98 bottles of beer.
Take one down and pass it around, 97 bottles of beer on the wall.

97 bottles of beer on the wall, 97 bottles of beer.
Take one down and pass it around, 96 bottles of beer on the wall.

96 bottles of beer on the wall, 96 bottles of beer.
Take one down and pass it around, 95 bottles of beer on the wall.

95 bottles of beer on the wall, 95 bottles of beer.
Take one down and pass it around, 94 bottles of beer on the wall.

94 bottles of beer on the wall, 94 bottles of beer.
Take one down and pass it around, 93 bottles of beer on the wall.

93 bottles of beer on the wall, 93 bottles of beer.
Take one down and pass it around, 92 bottles of beer on the wall.

92 bottles of beer on the wall, 92 bottles of beer.
Take one down and pass it around, 91 bottles of beer on the wall.

91 bottles of beer on the wall, 91 bottles of beer.
Take one down and pass it around, 90 bottles of beer on the wall.

90 bottles of beer on the wall, 90 bottles of beer.
Take one down and pass it around, 89 bottles of beer on the wall.

89 bottles of beer on the wall, 89 bottles of beer.
Take one down and pass it around, 88 bottles of beer on the wall.

88 bottles of beer on the wall, 88 bottles of beer.
Take one down and pass it around, 87 bottles of beer on the wall.

87 bottles of beer on the wall, 87 bottles of beer.
Take one down and pass it around, 86 bottles of beer on the wall.

86 bottles of beer on the wall, 86 bottles of beer.
Take one down and pass it around, 85 bottles of beer on the wall.

85 bottles of beer on the wall, 85 bottles of beer.
Take one down and pass it around, 84 bottles of beer on the wall.

84 bottles of beer on the wall, 84 bottles of beer.
Take one down and pass it around, 83 bottles of beer on the wall.

83 bottles of beer on the wall, 83 bottles of beer.
Take one down and pass it around, 82 bottles of beer on the wall.

82 bottles of beer on the wall, 82 bottles of beer.
Take one down and pass it around, 81 bottles of beer on the wall.

81 bottles of beer on the wall, 81 bottles of beer.
Take one down and pass it around, 80 bottles of beer on the wall.

80 bottles of beer on the wall, 80 bottles of beer.
Take one down and pass it around, 79 bottles of beer on the wall.

79 bottles of beer on the wall, 79 bottles of beer.
Take one down and pass it around, 78 bottles of beer on the wall.

78 bottles of beer on the wall, 78 bottles of beer.
Take one down and pass it around, 77 bottles of beer on the wall.

77 bottles of beer on the wall, 77 bottles of beer.
Take one down and pass it around, 76 bottles of beer on the wall.

76 bottles of beer on the wall, 76 bottles of beer.
Take one down and pass it around, 75 bottles of beer on the wall.

75 bottles of beer on the wall, 75 bottles of beer.
Take one down and pass it around, 74 bottles of beer on the wall.

74 bottles of beer on the wall, 74 bottles of beer.
Take one down and pass it around, 73 bottles of beer on the wall.

73 bottles of beer on the wall, 73 bottles of beer.
Take one down and pass it around, 72 bottles of beer on the wall.

72 bottles of beer on the wall, 72 bottles of beer.
Take one down and pass it around, 71 bottles of beer on the wall.

71 bottles of beer on the wall, 71 bottles of beer.
Take one down and pass it around, 70 bottles of beer on the wall.

70 bottles of beer on the wall, 70 bottles of beer.
Take one down and pass it around, 69 bottles of beer on the wall.

69 bottles of beer on the wall, 69 bottles of beer.
Take one down and pass it around, 68 bottles of beer on the wall.

68 bottles of beer on the wall, 68 bottles of beer.
Take one down and pass it around, 67 bottles of beer on the wall.

67 bottles of beer on the wall, 67 bottles of beer.
Take one down and pass it around, 66 bottles of beer on the wall.

66 bottles of beer on the wall, 66 bottles of beer.
Take one down and pass it around, 65 bottles of beer on the wall.

65 bottles of beer on the wall, 65 bottles of beer.
Take one down and pass it around, 64 bottles of beer on the wall.

64 bottles of beer on the wall, 64 bottles of beer.
Take one down and pass it around, 63 bottles of beer on the wall.

63 bottles of beer on the wall, 63 bottles of beer.
Take one down and pass it around, 62 bottles of beer on the wall.

62 bottles of beer on the wall, 62 bottles of beer.
Take one down and pass it around, 61 bottles of beer on the wall.

61 bottles of beer on the wall, 61 bottles of beer.
Take one down and pass it around, 60 bottles of beer on the wall.

60 bottles of beer on the wall, 60 bottles of beer.
Take one down and pass it around, 59 bottles of beer on the wall.

59 bottles of beer on the wall, 59 bottles of beer.
Take one down and pass it around, 58 bottles of beer on the wall.

58 bottles of beer on the wall, 58 bottles of beer.
Take one down and pass it around, 57 bottles of beer on the wall.

57 bottles of beer on the wall, 57 bottles of beer.
Take one down and pass it around, 56 bottles of beer on the wall.

56 bottles of beer on the wall, 56 bottles of beer.
Take one down and pass it around, 55 bottles of beer on the wall.

55 bottles of beer on the wall, 55 bottles of beer.
Take one down and pass it around, 54 bottles of beer on the wall.

54 bottles of beer on the wall, 54 bottles of beer.
Take one down and pass it around, 53 bottles of beer on the wall.

53 bottles of beer on the wall, 53 bottles of beer.
Take one down and pass it around, 52 bottles of beer on the wall.

52 bottles of beer on the wall, 52 bottles of beer.
Take one down and pass it around, 51 bottles of beer on the wall.

51 bottles of beer on the wall, 51 bottles of beer.
Take one down and pass it around, 50 bottles of beer on the wall.

50 bottles of beer on the wall, 50 bottles of beer.
Take one down and pass it around, 49 bottles of beer on the wall.

49 bottles of beer on the wall, 49 bottles of beer.
Take one down and pass it around, 48 bottles of beer on the wall.

48 bottles of beer on the wall, 48 bottles of beer.
Take one down and pass it around, 47 bottles of beer on the wall.

47 bottles of beer on the wall, 47 bottles of beer.
Take one down and pass it around, 46 bottles of beer on the wall.

46 bottles of beer on the wall, 46 bottles of beer.
Take one down and pass it around, 45 bottles of beer on the wall.

45 bottles of beer on the wall, 45 bottles of beer.
Take one down and pass it around, 44 bottles of beer on the wall.

44 bottles of beer on the wall, 44 bottles of beer.
Take one down and pass it around, 43 bottles of beer on the wall.

43 bottles of beer on the wall, 43 bottles of beer.
Take one down and pass it around, 42 bottles of beer on the wall.

42 bottles of beer on the wall, 42 bottles of beer.
Take one down and pass it around, 41 bottles of beer on the wall.

41 bottles of beer on the wall, 41 bottles of beer.
Take one down and pass it around, 40 bottles of beer on the wall.

40 bottles of beer on the wall, 40 bottles of beer.
Take one down and pass it around, 39 bottles of beer on the wall.

39 bottles of beer on the wall, 39 bottles of beer.
Take one down and pass it around, 38 bottles of beer on the wall.

38 bottles of beer on the wall, 38 bottles of beer.
Take one down and pass it around, 37 bottles of beer on the wall.

37 bottles of beer on the wall, 37 bottles of beer.
Take one down and pass it around, 36 bottles of beer on the wall.

36 bottles of beer on the wall, 36 bottles of beer.
Take one down and pass it around, 35 bottles of beer on the wall.

35 bottles of beer on the wall, 35 bottles of beer.
Take one down and pass it around, 34 bottles of beer on the wall.

34 bottles of beer on the wall, 34 bottles of beer.
Take one down and pass it around, 33 bottles of beer on the wall.

33 bottles of beer on the wall, 33 bottles of beer.
Take one down and pass it around, 32 bottles of beer on the wall.

32 bottles of beer on the wall, 32 bottles of beer.
Take one down and pass it around, 31 bottles of beer on the wall.

31 bottles of beer on the wall, 31 bottles of beer.
Take one down and pass it around, 30 bottles of beer on the wall.

30 bottles of beer on the wall, 30 bottles of beer.
Take one down and pass it around, 29 bottles of beer on the wall.

29 bottles of beer on the wall, 29 bottles of beer.
Take one down and pass it around, 28 bottles of beer on the wall.

28 bottles of beer on the wall, 28 bottles of beer.
Take one down and pass it around, 27 bottles of beer on the wall.

27 bottles of beer on the wall, 27 bottles of beer.
Take one down and pass it around, 26 bottles of beer on the wall.

26 bottles of beer on the wall, 26 bottles of beer.
Take one down and pass it around, 25 bottles of beer on the wall.

25 bottles of beer on the wall, 25 bottles of beer.
Take one down and pass it around, 24 bottles of beer on the wall.

24 bottles of beer on the wall, 24 bottles of beer.
Take one down and pass it around, 23 bottles of beer on the wall.

23 bottles of beer on the wall, 23 bottles of beer.
Take one down and pass it around, 22 bottles of beer on the wall.

22 bottles of beer on the wall, 22 bottles of beer.
Take one down and pass it around, 21 bottles of beer on the wall.

21 bottles of beer on the wall, 21 bottles of beer.
Take one down and pass it around, 20 bottles of beer on the wall.

20 bottles of beer on the wall, 20 bottles of beer.
Take one down and pass it around, 19 bottles of beer on the wall.

19 bottles of beer on the wall, 19 bottles of beer.
Take one down and pass it around, 18 bottles of beer on the wall.

18 bottles of beer on the wall, 18 bottles of beer.
Take one down and pass it around, 17 bottles of beer on the wall.

17 bottles of beer on the wall, 17 bottles of beer.
Take one down and pass it around, 16 bottles of beer on the wall.

16 bottles of beer on the wall, 16 bottles of beer.
Take one down and pass it around, 15 bottles of beer on the wall.

15 bottles of beer on the wall, 15 bottles of beer.
Take one down and pass it around, 14 bottles of beer on the wall.

14 bottles of beer on the wall, 14 bottles of beer.
Take one down and pass it around, 13 bottles of beer on the wall.

13 bottles of beer on the wall, 13 bottles of beer.
Take one down and pass it around, 12 bottles of beer on the wall.

12 bottles of beer on the wall, 12 bottles of beer.
Take one down and pass it around, 11 bottles of beer on the wall.

11 bottles of beer on the wall, 11 bottles of beer.
Take one down and pass it around, 10 bottles of beer on the wall.

10 bottles of beer on the wall, 10 bottles of beer.
Take one down and pass it around, 9 bottles of beer on the wall.

9 bottles of beer on the wall, 9 bottles of beer.
Take one down and pass it around, 8 bottles of beer on the wall.

8 bottles of beer on the wall, 8 bottles of beer.
Take one down and pass it around, 7 bottles of beer on the wall.

7 bottles of beer on the wall, 7 bottles of beer.
Take one down and pass it around, 6 bottles of beer on the wall.

6 bottles of beer on the wall, 6 bottles of beer.
Take one down and pass it around, 5 bottles of beer on the wall.

5 bottles of beer on the wall, 5 bottles of beer.
Take one down and pass it around, 4 bottles of beer on the wall.

4 bottles of beer on the wall, 4 bottles of beer.
Take one down and pass it around, 3 bottles of beer on the wall.

3 bottles of beer on the wall, 3 bottles of beer.
Take one down and pass it around, 2 bottles of beer on the wall.

2 bottles of beer on the wall, 2 bottles of beer.
Take one down and pass it around, 1 bottle of beer on the wall.

1 bottle of beer on the wall, 1 bottle of beer.
Take it down and pass it around, no more bottles of beer on the wall.

No more bottles of beer on the wall, no more bottles of beer.
Go to the store and buy some more, 99 bottles of beer on the wall.

For bonus points

Did you get the tests passing and the code clean? If you want to, these are some additional things you could try:

  • Remove as much duplication as you possibly can.
  • Optimize for readability, even if it means introducing duplication.
  • If you've removed all the duplication, do you have a lot of conditionals? Try replacing the conditionals with polymorphism, if it applies in this language. How readable is it?

Then please share your thoughts in a comment on the submission. Did this experiment make the code better? Worse? Did you learn anything from it?

Running the tests

You can run all the tests for an exercise by entering

$ gradle test

in your terminal.

Source

Learn to Program by Chris Pine http://pine.fm/LearnToProgram/?Chapter=06

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

BeerSongTest.java

import org.junit.Test;
import org.junit.Ignore;
import org.junit.Before;

import static org.junit.Assert.assertEquals;

public class BeerSongTest {

    private BeerSong beerSong;

    @Before
    public void setup() {
        beerSong = new BeerSong();
    }

    @Test
    public void singFirstVerse() {
        assertEquals("99 bottles of beer on the wall, 99 bottles of beer.\n" +
                        "Take one down and pass it around, 98 bottles of beer on the wall.\n\n",
                beerSong.sing(99, 1));
    }

    @Ignore("Remove to run test")
    @Test
    public void singLastGenericVerse() {
        assertEquals("3 bottles of beer on the wall, 3 bottles of beer.\n" +
                        "Take one down and pass it around, 2 bottles of beer on the wall.\n\n",
                beerSong.sing(3, 1));
    }

    @Ignore("Remove to run test")
    @Test
    public void verseWithTwoBottles() {
        assertEquals("2 bottles of beer on the wall, 2 bottles of beer.\n" +
                        "Take one down and pass it around, 1 bottle of beer on the wall.\n\n",
                beerSong.sing(2, 1));
    }

    @Ignore("Remove to run test")
    @Test
    public void verseWithOneBottle() {
        assertEquals("1 bottle of beer on the wall, 1 bottle of beer.\n" +
                        "Take it down and pass it around, no more bottles of beer on the wall.\n\n",
                beerSong.sing(1, 1));
    }

    @Ignore("Remove to run test")
    @Test
    public void verseWithZeroBottles() {
        assertEquals("No more bottles of beer on the wall, no more bottles of beer.\n" +
                        "Go to the store and buy some more, 99 bottles of beer on the wall.\n\n",
                beerSong.sing(0, 1));
    }

    @Ignore("Remove to run test")
    @Test
    public void singFirstTwoVerses() {
        assertEquals("99 bottles of beer on the wall, 99 bottles of beer.\n" +
                        "Take one down and pass it around, 98 bottles of beer on the wall.\n\n" +
                        "98 bottles of beer on the wall, 98 bottles of beer.\n" +
                        "Take one down and pass it around, 97 bottles of beer on the wall.\n\n",
                beerSong.sing(99, 2));
    }

    @Ignore("Remove to run test")
    @Test
    public void singLastThreeVerses() {
        assertEquals("2 bottles of beer on the wall, 2 bottles of beer.\n" +
                        "Take one down and pass it around, 1 bottle of beer on the wall.\n\n" +
                        "1 bottle of beer on the wall, 1 bottle of beer.\n" +
                        "Take it down and pass it around, no more bottles of beer on the wall.\n\n" +
                        "No more bottles of beer on the wall, no more bottles of beer.\n" +
                        "Go to the store and buy some more, 99 bottles of beer on the wall.\n\n",
                beerSong.sing(2, 3));
    }

    @Ignore("Remove to run test")
    @Test
    public void singEntireSong() {
        assertEquals("99 bottles of beer on the wall, 99 bottles of beer.\nTake one down and pass it around, " +
                     "98 bottles of beer on the wall.\n\n" +
                     "98 bottles of beer on the wall, 98 bottles of beer.\nTake one down and pass it around, " +
                     "97 bottles of beer on the wall.\n\n" +
                     "97 bottles of beer on the wall, 97 bottles of beer.\nTake one down and pass it around, " +
                     "96 bottles of beer on the wall.\n\n" +
                     "96 bottles of beer on the wall, 96 bottles of beer.\nTake one down and pass it around, " +
                     "95 bottles of beer on the wall.\n\n" +
                     "95 bottles of beer on the wall, 95 bottles of beer.\nTake one down and pass it around, " +
                     "94 bottles of beer on the wall.\n\n" +
                     "94 bottles of beer on the wall, 94 bottles of beer.\nTake one down and pass it around, " +
                     "93 bottles of beer on the wall.\n\n" +
                     "93 bottles of beer on the wall, 93 bottles of beer.\nTake one down and pass it around, " +
                     "92 bottles of beer on the wall.\n\n" +
                     "92 bottles of beer on the wall, 92 bottles of beer.\nTake one down and pass it around, " +
                     "91 bottles of beer on the wall.\n\n" +
                     "91 bottles of beer on the wall, 91 bottles of beer.\nTake one down and pass it around, " +
                     "90 bottles of beer on the wall.\n\n" +
                     "90 bottles of beer on the wall, 90 bottles of beer.\nTake one down and pass it around, " +
                     "89 bottles of beer on the wall.\n\n" +
                     "89 bottles of beer on the wall, 89 bottles of beer.\nTake one down and pass it around, " +
                     "88 bottles of beer on the wall.\n\n" +
                     "88 bottles of beer on the wall, 88 bottles of beer.\nTake one down and pass it around, " +
                     "87 bottles of beer on the wall.\n\n" +
                     "87 bottles of beer on the wall, 87 bottles of beer.\nTake one down and pass it around, " +
                     "86 bottles of beer on the wall.\n\n" +
                     "86 bottles of beer on the wall, 86 bottles of beer.\nTake one down and pass it around, " +
                     "85 bottles of beer on the wall.\n\n" +
                     "85 bottles of beer on the wall, 85 bottles of beer.\nTake one down and pass it around, " +
                     "84 bottles of beer on the wall.\n\n" +
                     "84 bottles of beer on the wall, 84 bottles of beer.\nTake one down and pass it around, " +
                     "83 bottles of beer on the wall.\n\n" +
                     "83 bottles of beer on the wall, 83 bottles of beer.\nTake one down and pass it around, " +
                     "82 bottles of beer on the wall.\n\n" +
                     "82 bottles of beer on the wall, 82 bottles of beer.\nTake one down and pass it around, " +
                     "81 bottles of beer on the wall.\n\n" +
                     "81 bottles of beer on the wall, 81 bottles of beer.\nTake one down and pass it around, " +
                     "80 bottles of beer on the wall.\n\n" +
                     "80 bottles of beer on the wall, 80 bottles of beer.\nTake one down and pass it around, " +
                     "79 bottles of beer on the wall.\n\n" +
                     "79 bottles of beer on the wall, 79 bottles of beer.\nTake one down and pass it around, " +
                     "78 bottles of beer on the wall.\n\n" +
                     "78 bottles of beer on the wall, 78 bottles of beer.\nTake one down and pass it around, " +
                     "77 bottles of beer on the wall.\n\n" +
                     "77 bottles of beer on the wall, 77 bottles of beer.\nTake one down and pass it around, " +
                     "76 bottles of beer on the wall.\n\n" +
                     "76 bottles of beer on the wall, 76 bottles of beer.\nTake one down and pass it around, " +
                     "75 bottles of beer on the wall.\n\n" +
                     "75 bottles of beer on the wall, 75 bottles of beer.\nTake one down and pass it around, " +
                     "74 bottles of beer on the wall.\n\n" +
                     "74 bottles of beer on the wall, 74 bottles of beer.\nTake one down and pass it around, " +
                     "73 bottles of beer on the wall.\n\n" +
                     "73 bottles of beer on the wall, 73 bottles of beer.\nTake one down and pass it around, " +
                     "72 bottles of beer on the wall.\n\n" +
                     "72 bottles of beer on the wall, 72 bottles of beer.\nTake one down and pass it around, " +
                     "71 bottles of beer on the wall.\n\n" +
                     "71 bottles of beer on the wall, 71 bottles of beer.\nTake one down and pass it around, " +
                     "70 bottles of beer on the wall.\n\n" +
                     "70 bottles of beer on the wall, 70 bottles of beer.\nTake one down and pass it around, " +
                     "69 bottles of beer on the wall.\n\n" +
                     "69 bottles of beer on the wall, 69 bottles of beer.\nTake one down and pass it around, " +
                     "68 bottles of beer on the wall.\n\n" +
                     "68 bottles of beer on the wall, 68 bottles of beer.\nTake one down and pass it around, " +
                     "67 bottles of beer on the wall.\n\n" +
                     "67 bottles of beer on the wall, 67 bottles of beer.\nTake one down and pass it around, " +
                     "66 bottles of beer on the wall.\n\n" +
                     "66 bottles of beer on the wall, 66 bottles of beer.\nTake one down and pass it around, " +
                     "65 bottles of beer on the wall.\n\n" +
                     "65 bottles of beer on the wall, 65 bottles of beer.\nTake one down and pass it around, " +
                     "64 bottles of beer on the wall.\n\n" +
                     "64 bottles of beer on the wall, 64 bottles of beer.\nTake one down and pass it around, " +
                     "63 bottles of beer on the wall.\n\n" +
                     "63 bottles of beer on the wall, 63 bottles of beer.\nTake one down and pass it around, " +
                     "62 bottles of beer on the wall.\n\n" +
                     "62 bottles of beer on the wall, 62 bottles of beer.\nTake one down and pass it around, " +
                     "61 bottles of beer on the wall.\n\n" +
                     "61 bottles of beer on the wall, 61 bottles of beer.\nTake one down and pass it around, " +
                     "60 bottles of beer on the wall.\n\n" +
                     "60 bottles of beer on the wall, 60 bottles of beer.\nTake one down and pass it around, " +
                     "59 bottles of beer on the wall.\n\n" +
                     "59 bottles of beer on the wall, 59 bottles of beer.\nTake one down and pass it around, " +
                     "58 bottles of beer on the wall.\n\n" +
                     "58 bottles of beer on the wall, 58 bottles of beer.\nTake one down and pass it around, " +
                     "57 bottles of beer on the wall.\n\n" +
                     "57 bottles of beer on the wall, 57 bottles of beer.\nTake one down and pass it around, " +
                     "56 bottles of beer on the wall.\n\n" +
                     "56 bottles of beer on the wall, 56 bottles of beer.\nTake one down and pass it around, " +
                     "55 bottles of beer on the wall.\n\n" +
                     "55 bottles of beer on the wall, 55 bottles of beer.\nTake one down and pass it around, " +
                     "54 bottles of beer on the wall.\n\n" +
                     "54 bottles of beer on the wall, 54 bottles of beer.\nTake one down and pass it around, " +
                     "53 bottles of beer on the wall.\n\n" +
                     "53 bottles of beer on the wall, 53 bottles of beer.\nTake one down and pass it around, " +
                     "52 bottles of beer on the wall.\n\n" +
                     "52 bottles of beer on the wall, 52 bottles of beer.\nTake one down and pass it around, " +
                     "51 bottles of beer on the wall.\n\n" +
                     "51 bottles of beer on the wall, 51 bottles of beer.\nTake one down and pass it around, " +
                     "50 bottles of beer on the wall.\n\n" +
                     "50 bottles of beer on the wall, 50 bottles of beer.\nTake one down and pass it around, " +
                     "49 bottles of beer on the wall.\n\n" +
                     "49 bottles of beer on the wall, 49 bottles of beer.\nTake one down and pass it around, " +
                     "48 bottles of beer on the wall.\n\n" +
                     "48 bottles of beer on the wall, 48 bottles of beer.\nTake one down and pass it around, " +
                     "47 bottles of beer on the wall.\n\n" +
                     "47 bottles of beer on the wall, 47 bottles of beer.\nTake one down and pass it around, " +
                     "46 bottles of beer on the wall.\n\n" +
                     "46 bottles of beer on the wall, 46 bottles of beer.\nTake one down and pass it around, " +
                     "45 bottles of beer on the wall.\n\n" +
                     "45 bottles of beer on the wall, 45 bottles of beer.\nTake one down and pass it around, " +
                     "44 bottles of beer on the wall.\n\n" +
                     "44 bottles of beer on the wall, 44 bottles of beer.\nTake one down and pass it around, " +
                     "43 bottles of beer on the wall.\n\n" +
                     "43 bottles of beer on the wall, 43 bottles of beer.\nTake one down and pass it around, " +
                     "42 bottles of beer on the wall.\n\n" +
                     "42 bottles of beer on the wall, 42 bottles of beer.\nTake one down and pass it around, " +
                     "41 bottles of beer on the wall.\n\n" +
                     "41 bottles of beer on the wall, 41 bottles of beer.\nTake one down and pass it around, " +
                     "40 bottles of beer on the wall.\n\n" +
                     "40 bottles of beer on the wall, 40 bottles of beer.\nTake one down and pass it around, " +
                     "39 bottles of beer on the wall.\n\n" +
                     "39 bottles of beer on the wall, 39 bottles of beer.\nTake one down and pass it around, " +
                     "38 bottles of beer on the wall.\n\n" +
                     "38 bottles of beer on the wall, 38 bottles of beer.\nTake one down and pass it around, " +
                     "37 bottles of beer on the wall.\n\n" +
                     "37 bottles of beer on the wall, 37 bottles of beer.\nTake one down and pass it around, " +
                     "36 bottles of beer on the wall.\n\n" +
                     "36 bottles of beer on the wall, 36 bottles of beer.\nTake one down and pass it around, " +
                     "35 bottles of beer on the wall.\n\n" +
                     "35 bottles of beer on the wall, 35 bottles of beer.\nTake one down and pass it around, " +
                     "34 bottles of beer on the wall.\n\n" +
                     "34 bottles of beer on the wall, 34 bottles of beer.\nTake one down and pass it around, " +
                     "33 bottles of beer on the wall.\n\n" +
                     "33 bottles of beer on the wall, 33 bottles of beer.\nTake one down and pass it around, " +
                     "32 bottles of beer on the wall.\n\n" +
                     "32 bottles of beer on the wall, 32 bottles of beer.\nTake one down and pass it around, " +
                     "31 bottles of beer on the wall.\n\n" +
                     "31 bottles of beer on the wall, 31 bottles of beer.\nTake one down and pass it around, " +
                     "30 bottles of beer on the wall.\n\n" +
                     "30 bottles of beer on the wall, 30 bottles of beer.\nTake one down and pass it around, " +
                     "29 bottles of beer on the wall.\n\n" +
                     "29 bottles of beer on the wall, 29 bottles of beer.\nTake one down and pass it around, " +
                     "28 bottles of beer on the wall.\n\n" +
                     "28 bottles of beer on the wall, 28 bottles of beer.\nTake one down and pass it around, " +
                     "27 bottles of beer on the wall.\n\n" +
                     "27 bottles of beer on the wall, 27 bottles of beer.\nTake one down and pass it around, " +
                     "26 bottles of beer on the wall.\n\n" +
                     "26 bottles of beer on the wall, 26 bottles of beer.\nTake one down and pass it around, " +
                     "25 bottles of beer on the wall.\n\n" +
                     "25 bottles of beer on the wall, 25 bottles of beer.\nTake one down and pass it around, " +
                     "24 bottles of beer on the wall.\n\n" +
                     "24 bottles of beer on the wall, 24 bottles of beer.\nTake one down and pass it around, " +
                     "23 bottles of beer on the wall.\n\n" +
                     "23 bottles of beer on the wall, 23 bottles of beer.\nTake one down and pass it around, " +
                     "22 bottles of beer on the wall.\n\n" +
                     "22 bottles of beer on the wall, 22 bottles of beer.\nTake one down and pass it around, " +
                     "21 bottles of beer on the wall.\n\n" +
                     "21 bottles of beer on the wall, 21 bottles of beer.\nTake one down and pass it around, " +
                     "20 bottles of beer on the wall.\n\n" +
                     "20 bottles of beer on the wall, 20 bottles of beer.\nTake one down and pass it around, " +
                     "19 bottles of beer on the wall.\n\n" +
                     "19 bottles of beer on the wall, 19 bottles of beer.\nTake one down and pass it around, " +
                     "18 bottles of beer on the wall.\n\n" +
                     "18 bottles of beer on the wall, 18 bottles of beer.\nTake one down and pass it around, " +
                     "17 bottles of beer on the wall.\n\n" +
                     "17 bottles of beer on the wall, 17 bottles of beer.\nTake one down and pass it around, " +
                     "16 bottles of beer on the wall.\n\n" +
                     "16 bottles of beer on the wall, 16 bottles of beer.\nTake one down and pass it around, " +
                     "15 bottles of beer on the wall.\n\n" +
                     "15 bottles of beer on the wall, 15 bottles of beer.\nTake one down and pass it around, " +
                     "14 bottles of beer on the wall.\n\n" +
                     "14 bottles of beer on the wall, 14 bottles of beer.\nTake one down and pass it around, " +
                     "13 bottles of beer on the wall.\n\n" +
                     "13 bottles of beer on the wall, 13 bottles of beer.\nTake one down and pass it around, " +
                     "12 bottles of beer on the wall.\n\n" +
                     "12 bottles of beer on the wall, 12 bottles of beer.\nTake one down and pass it around, " +
                     "11 bottles of beer on the wall.\n\n" +
                     "11 bottles of beer on the wall, 11 bottles of beer.\nTake one down and pass it around, " +
                     "10 bottles of beer on the wall.\n\n" +
                     "10 bottles of beer on the wall, 10 bottles of beer.\nTake one down and pass it around, " +
                     "9 bottles of beer on the wall.\n\n" +
                     "9 bottles of beer on the wall, 9 bottles of beer.\nTake one down and pass it around, " +
                     "8 bottles of beer on the wall.\n\n" +
                     "8 bottles of beer on the wall, 8 bottles of beer.\nTake one down and pass it around, " +
                     "7 bottles of beer on the wall.\n\n" +
                     "7 bottles of beer on the wall, 7 bottles of beer.\nTake one down and pass it around, " +
                     "6 bottles of beer on the wall.\n\n" +
                     "6 bottles of beer on the wall, 6 bottles of beer.\nTake one down and pass it around, " +
                     "5 bottles of beer on the wall.\n\n" +
                     "5 bottles of beer on the wall, 5 bottles of beer.\nTake one down and pass it around, " +
                     "4 bottles of beer on the wall.\n\n" +
                     "4 bottles of beer on the wall, 4 bottles of beer.\nTake one down and pass it around, " +
                     "3 bottles of beer on the wall.\n\n" +
                     "3 bottles of beer on the wall, 3 bottles of beer.\nTake one down and pass it around, " +
                     "2 bottles of beer on the wall.\n\n" +
                     "2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, " +
                     "1 bottle of beer on the wall.\n\n" +
                     "1 bottle of beer on the wall, 1 bottle of beer.\nTake it down and pass it around, " +
                     "no more bottles of beer on the wall.\n\n" +
                     "No more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy " +
                     "some more, 99 bottles of beer on the wall.\n\n",
                beerSong.singSong());
    }

}
class BeerSong {
    String sing(int countOfBottles, int countOfBottlesPassed) {
        if (countOfBottles < 0 || countOfBottlesPassed < 0 || countOfBottles + 1 < countOfBottlesPassed) {
            return "";
        }
        StringBuilder result = new StringBuilder();
        for (int i = 0; i < countOfBottlesPassed; i++) {
            Bottle bottle = getBottles(countOfBottles - i);
            result.append(bottle.getVerse());
        }
        return result.toString();
    }

    String singSong() {
        return sing(99, 100);
    }

    private Bottle getBottles(int countOfBottles) {
        if (countOfBottles == 0) {
            return new NoBottle();
        }
        if (countOfBottles == 1) {
            return new OneBottle();
        }
        if (countOfBottles == 2) {
            return new TwoBottles();
        }
        return new MoreThanTwoBottles(countOfBottles);
    }

    private abstract class Bottle {
        protected abstract String getFirstLine();

        protected abstract String getSecondLine();

        private String getVerse() {
            return getFirstLine() + getSecondLine();
        }
    }

    private class NoBottle extends Bottle {
        @Override
        protected String getFirstLine() {
            return "No more bottles of beer on the wall, no more bottles of beer.\n";
        }

        @Override
        protected String getSecondLine() {
            return "Go to the store and buy some more, 99 bottles of beer on the wall.\n\n";
        }
    }

    private class OneBottle extends Bottle {
        @Override
        protected String getFirstLine() {
            return "1 bottle of beer on the wall, 1 bottle of beer.\n";
        }

        @Override
        protected String getSecondLine() {
            return "Take it down and pass it around, no more bottles of beer on the wall.\n\n";
        }
    }

    private class TwoBottles extends Bottle {
        @Override
        protected String getFirstLine() {
            return "2 bottles of beer on the wall, 2 bottles of beer.\n";
        }

        @Override
        protected String getSecondLine() {
            return "Take one down and pass it around, 1 bottle of beer on the wall.\n\n";
        }
    }

    private class MoreThanTwoBottles extends Bottle {
        private int countOfBottles;

        private MoreThanTwoBottles(int countOfBottles) {
            this.countOfBottles = countOfBottles;
        }

        @Override
        protected String getFirstLine() {
            return String.format("%1$s bottles of beer on the wall, %1$s bottles of beer.\n", countOfBottles);
        }

        @Override
        protected String getSecondLine() {
            return String.format("Take one down and pass it around, %1$s bottles of beer on the wall.\n\n", countOfBottles - 1);
        }
    }
}

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