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artemkorsakov's solution

to Proverb in the Java Track

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

For want of a horseshoe nail, a kingdom was lost, or so the saying goes.

Given a list of inputs, generate the relevant proverb. For example, given the list ["nail", "shoe", "horse", "rider", "message", "battle", "kingdom"], you will output the full text of this proverbial rhyme:

For want of a nail the shoe was lost.
For want of a shoe the horse was lost.
For want of a horse the rider was lost.
For want of a rider the message was lost.
For want of a message the battle was lost.
For want of a battle the kingdom was lost.
And all for the want of a nail.

Note that the list of inputs may vary; your solution should be able to handle lists of arbitrary length and content. No line of the output text should be a static, unchanging string; all should vary according to the input given.

Running the tests

You can run all the tests for an exercise by entering

$ gradle test

in your terminal.

Source

Wikipedia http://en.wikipedia.org/wiki/For_Want_of_a_Nail

Submitting Incomplete Solutions

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

ProverbTest.java

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

import static org.hamcrest.CoreMatchers.is;
import static org.junit.Assert.assertThat;

public class ProverbTest {

    @Test
    public void zeroWordsAreGiven() {
        String[] words  = new String[0];
        String proverb  = new Proverb(words).recite(),
               expected = "";

        assertThat(proverb, is(expected));
    }

    @Ignore("Remove to run test")
    @Test
    public void singlePieceOfProverb() {
        String[] words  = new String[]{"nail"};
        String proverb  = new Proverb(words).recite(),
               expected = "And all for the want of a nail.";

        assertThat(proverb, is(expected));
    }

    @Ignore("Remove to run test")
    @Test
    public void twoPiecesOfProverb() {
        String[] words  = new String[]{"nail", "shoe"};
        String proverb  = new Proverb(words).recite(),
               expected = "For want of a nail the shoe was lost.\n" +
                          "And all for the want of a nail.";

        assertThat(proverb, is(expected));
    }

    @Ignore("Remove to run test")
    @Test
    public void shortChainOfConsequences() {
        String[] words  = new String[]{"nail", "shoe", "horse"};
        String proverb  = new Proverb(words).recite(),
               expected = "For want of a nail the shoe was lost.\n" +
                          "For want of a shoe the horse was lost.\n" +
                          "And all for the want of a nail.";

        assertThat(proverb, is(expected));
    }

    @Ignore("Remove to run test")
    @Test
    public void fullProverb() {
        String[] words  = new String[]{"nail", "shoe", "horse", "rider", "message", "battle", "kingdom"};
        String proverb  = new Proverb(words).recite(),
               expected = "For want of a nail the shoe was lost.\n" +
                          "For want of a shoe the horse was lost.\n" +
                          "For want of a horse the rider was lost.\n" +
                          "For want of a rider the message was lost.\n" +
                          "For want of a message the battle was lost.\n" +
                          "For want of a battle the kingdom was lost.\n" +
                          "And all for the want of a nail.";

        assertThat(proverb, is(expected));
    }

    @Ignore("Remove to run test")
    @Test
    public void fourPiecesModernizedProverb() {
        String[] words  = new String[]{"pin", "gun", "soldier", "battle"};
        String proverb  = new Proverb(words).recite(),
               expected = "For want of a pin the gun was lost.\n" +
                          "For want of a gun the soldier was lost.\n" +
                          "For want of a soldier the battle was lost.\n" +
                          "And all for the want of a pin.";

        assertThat(proverb, is(expected));
    }

}
class Proverb {
    private String[] words;

    Proverb(String[] words) {
        this.words = words;
    }

    String recite() {
        if (words.length == 0) {
            return "";
        }

        StringBuilder result = new StringBuilder();
        for (int i = 0; i < words.length - 1; i++) {
            result.append(String.format("For want of a %1$s the %2$s was lost.\n", words[i], words[i + 1]));
        }
        result.append(String.format("And all for the want of a %s.", words[0]));
        return result.toString();
    }

}

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