ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');
const result = INPUT.reduce((total, _lwh) => {
  const lwh = _lwh.split('x');
  const length = lwh[0];
  const width = lwh[1];
  const height = lwh[2];

  return total
    + (2 * length * width)

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');
const result = INPUT.reduce((total, _lwh) => {
  const lwh = _lwh.split('x').map(Number).sort((a, b) => a - b);

  return total
    + (lwh[0] + lwh[0] + lwh[1] + lwh[1])
    + (lwh[0] * lwh[1] * lwh[2])
}, 0);

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('');

// Unique set of coordinates with the starting coordinates already added
const coordinates = new Set().add(`0x0`);

INPUT.reduce((curCoords, direction) => {
  let newCoords = {x: 0, y: 0};

  if (direction === '^') newCoords = {x: curCoords.x, y: curCoords.y + 1};

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('');
const santaDirections = INPUT.filter((item, index) => index % 2 === 0);
const roboSantaDirections = INPUT.filter((item, index) => index % 2 === 1);

// Get array of directions and return array of visited coordinates
const traverse = directions => {
  let visitedCoordinates = ['0x0'];
  let currentPosition = {x: 0, y: 0};

ghaiklor

const crypto = require('crypto');
const INPUT = 'ckczppom';
const md5 = data => crypto.createHash('md5').update(data).digest('hex');
const isStartsWithFiveZeros = data => data.slice(0, 5) === '00000';

let counter = 0;
while (!isStartsWithFiveZeros(md5(`${INPUT}${counter}`))) counter++;

console.log(counter);

ghaiklor

const crypto = require('crypto');
const INPUT = 'ckczppom';
const md5 = data => crypto.createHash('md5').update(data).digest('hex');
const isStartsWithSixZeros = data => data.slice(0, 6) === '000000';

let counter = 0;
while (!isStartsWithSixZeros(md5(`${INPUT}${counter}`))) counter++;

console.log(counter);

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');

// Dictionary of letters that need to be checked against the rules
const VOWELS = ['a', 'e', 'i', 'o', 'u'];
const DOUBLE_LETTERS = 'abcdefghijklmnopqrstuvwxyz'.split('').map(item => item + item);
const RESTRICTED_LETTERS = ['ab', 'cd', 'pq', 'xy'];

// Methods to check the rules
const isContainThreeVowels = string => string.split('').reduce((vowels, char) => VOWELS.indexOf(char) === -1 ? vowels : ++vowels, 0) >= 3;

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');

// Part 1 was written with pure functions but Part 2 I've decided to write with RegExp
const isContainPair = string => /([a-z][a-z]).*\1/.test(string);
const isContainRepeatLetter = string => /([a-z])[a-z]\1/.test(string);

const isNiceString = string => !!(isContainPair(string) && isContainRepeatLetter(string));

const result = INPUT.reduce((total, string) => isNiceString(string) ? ++total : total, 0);

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');

// Parse command from string and return object
const parseCommand = _command => {
  let command = _command.match(/(turn on|turn off|toggle) (\d+),(\d+) through (\d+),(\d+)/);
  return {command: command[1], x1: +command[2], y1: +command[3], x2: +command[4], y2: +command[5]};
};

// Map of our lights

ghaiklor

const fs = require('fs');
const INPUT = fs.readFileSync('./input.txt', 'utf-8').split('\n');
const COMMANDS_REGEX = /(turn on|turn off|toggle) (\d+),(\d+) through (\d+),(\d+)/;

// Parse command from string and return object
const parseCommand = _command => {
  let command = _command.match(COMMANDS_REGEX);
  return {command: command[1], x1: +command[2], y1: +command[3], x2: +command[4], y2: +command[5]};
};