Talented problems

array.js

Array.range = function(start, count) {
  return Array.apply(null, Array(count)).map((e, i) => start + i);
}

Array.prototype.sum = function() {
  return this.reduce((prev, next) => prev + next, 0);
}

BingoCard.js

function getCard() {
  const bCards = createCards(5, 'B', 1, 15);
  const iCards = createCards(5, 'I', 16, 30);
  const nCards = createCards(4, 'N', 31, 45);
  const gCards = createCards(5, 'G', 46, 60);
  const oCards = createCards(5, 'O', 61, 75);
  return [].concat.apply(bCards, [iCards, nCards, gCards, oCards]);
}

function createCards (amount, letter, min, max) {
  const cards = [];
  for (let i = 0; i < amount; i++) {
    let element;
    while (!element || cards.includes(element)) {
      element = letter + getRandomInt(min, max);
    }
    cards.push(element);
  }
  return cards;
}

function getRandomInt (min, max) {
  return Math.floor(Math.random() * (max - min + 1)) + min;
}

Car.js

function CarOld (model, registerNumber, color) {
  	this.color = color;
	this.paint = function (color) {
		this.color = color;
    };
	Object.defineProperties(this, {
		'model': {value: model, writable: false},
		'registerNumber': {value: registerNumber, writable: false},
		'color': {value: this.color},
		'paint': {value: this.paint}
    })
}

class Car {
  constructor (model, registerNumber, color) {
    this._model = model;
    this._registerNumber = registerNumber;
    this._color = color;
  }

  paint (color) {
    this.color = color;
  }

  get model () {
    return this._model;
  }
  get registerNumber () {
    return this._registerNumber;
  }
  set color (color) {
    this._color = color;
  }
  get color () {
    return this._color;
  }
}

fibonacci.js

function fib (n, x, y) {
    if (n < 1) return;
    console.log(n, x);
    n--;
    fib(n, y, x+y);
}

fib (100, 0, 1);

flattenArray.js

function flattenArray (arr) {
  return arr.reduce((acc, next) => {
    if (Array.isArray(next)) {
      return acc.concat(flattenArray(next));
    } else {
      return acc.concat(next);
    }
  }, []).filter(it => !!it);
}