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nahuel-ianni's solution

to Scrabble Score in the JavaScript Track

Published at Oct 20 2020 · 0 comments
Instructions
Test suite
Solution

Given a word, compute the scrabble score for that word.

Letter Values

You'll need these:

Letter                           Value
A, E, I, O, U, L, N, R, S, T       1
D, G                               2
B, C, M, P                         3
F, H, V, W, Y                      4
K                                  5
J, X                               8
Q, Z                               10

Examples

"cabbage" should be scored as worth 14 points:

  • 3 points for C
  • 1 point for A, twice
  • 3 points for B, twice
  • 2 points for G
  • 1 point for E

And to total:

  • 3 + 2*1 + 2*3 + 2 + 1
  • = 3 + 2 + 6 + 3
  • = 5 + 9
  • = 14

Extensions

  • You can play a double or a triple letter.
  • You can play a double or a triple word.

Setup

Go through the setup instructions for Javascript to install the necessary dependencies:

https://exercism.io/tracks/javascript/installation

Requirements

Please cd into exercise directory before running all below commands.

Install assignment dependencies:

$ npm install

Making the test suite pass

Execute the tests with:

$ npm test

In the test suites all tests but the first have been skipped.

Once you get a test passing, you can enable the next one by changing xtest to test.

Submitting Solutions

Once you have a solution ready, you can submit it using:

exercism submit scrabble-score.js

Submitting Incomplete Solutions

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

Exercise Source Credits

Inspired by the Extreme Startup game https://github.com/rchatley/extreme_startup

scrabble-score.spec.js

import { score } from './scrabble-score';

describe('Scrabble', () => {
  test('lowercase letter', () => {
    expect(score('a')).toEqual(1);
  });

  xtest('uppercase letter', () => {
    expect(score('A')).toEqual(1);
  });

  xtest('valuable letter', () => {
    expect(score('f')).toEqual(4);
  });

  xtest('short word', () => {
    expect(score('at')).toEqual(2);
  });

  xtest('short, valuable word', () => {
    expect(score('zoo')).toEqual(12);
  });

  xtest('medium word', () => {
    expect(score('street')).toEqual(6);
  });

  xtest('medium, valuable word', () => {
    expect(score('quirky')).toEqual(22);
  });

  xtest('long, mixed-case word', () => {
    expect(score('OxyphenButazone')).toEqual(41);
  });

  xtest('english-like word', () => {
    expect(score('pinata')).toEqual(8);
  });

  xtest('empty input', () => {
    expect(score('')).toEqual(0);
  });

  xtest('entire alphabet available', () => {
    expect(score('abcdefghijklmnopqrstuvwxyz')).toEqual(87);
  });
});
const scoreTable = {
  1: ['a', 'e', 'i', 'o', 'u', 'l', 'n', 'r', 's', 't'],
  2: ['d', 'g'],
  3: ['b', 'c', 'm', 'p'],
  4: ['f', 'h', 'v', 'w', 'y'],
  5: ['k'],
  8: ['j', 'x'],
  10: ['q', 'z']
};

const getScore = (char) => {
  for (let value in scoreTable)
    if (scoreTable[value].includes(char)) return Number(value);
}

export const score = (word) =>
  [...word]
    .map(char => getScore(char.toLowerCase()))
    .reduce((sum, value) => { return sum + value }, 0);

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