Advent Of Code 2016 Day 1 created by joeinnes - https://repl.it/EfFK/24

Advent Of Code 2016 Day 1.js

const input = 'R3, L2, L2, R4, L1, R2, R3, R4, L2, R4, L2, L5, L1, R5, R2, R2, L1, R4, R1, L5, L3, R4, R3, R1, L1, L5, L4, L2, R5, L3, L4, R3, R1, L3, R1, L3, R3, L4, R2, R5, L190, R2, L3, R47, R4, L3, R78, L1, R3, R190, R4, L3, R4, R2, R5, R3, R4, R3, L1, L4, R3, L4, R1, L4, L5, R3, L3, L4, R1, R2, L4, L3, R3, R3, L2, L5, R1, L4, L1, R5, L5, R1, R5, L4, R2, L2, R1, L5, L4, R4, R4, R3, R2, R3, L1, R4, R5, L2, L5, L4, L1, R4, L4, R4, L4, R1, R5, L1, R1, L5, R5, R1, R1, L3, L1, R4, L1, L4, L4, L3, R1, R4, R1, R1, R2, L5, L2, R4, L1, R3, L5, L2, R5, L4, R5, L5, R3, R4, L3, L3, L2, R2, L5, L5, R3, R4, R3, R4, R3, R1'
const inputArray = input.split(', ')

function mover() {
  this.xPos = 0
  this.yPos = 0
  this.heading = 0
  this.visited = []
  this.visitedTwice = []
  this.turn = (direction) => {
    if (direction === 'R') {
      this.heading++
    } else {
      this.heading--
    }
    if (this.heading > 3) {
      this.heading = 0
    }
    if (this.heading < 0) {
      this.heading = 3
    }
  }
  this.move = (distance) => {
    switch(this.heading) {
      case 0:
        this.yPos += distance
        break
      case 1:
        this.xPos += distance
        break
      case 2:
        this.yPos -= distance
        break
      case 3:
        this.xPos -= distance
        break
    }
  }
  this.hasBeenHereBefore = () => {
    let returnValue = false
    let locationString = `x${this.xPos}y${this.yPos}`
    if (this.visited.indexOf(locationString) > -1) {
      returnValue = true
    }
    this.visited.push(`x${this.xPos}y${this.yPos}`)
    return returnValue
  }
}

function part1 () {
  let Santa = new mover()
  inputArray.forEach((instruction) => {
    let turnDirection = instruction[0]
    let distance = parseInt(instruction.substring(1))
    Santa.turn(turnDirection)
    Santa.move(distance)
  })
  return Santa.xPos + Santa.yPos
}

function part2 () {
  let SecondSanta = new mover()
  inputArray.forEach((instruction) => {
    let turnDirection = instruction[0]
    let distance = parseInt(instruction.substring(1))
    SecondSanta.turn(turnDirection)
    while (distance) {
      SecondSanta.move(1)
      if (SecondSanta.hasBeenHereBefore()) {
        SecondSanta.visitedTwice.push({x: SecondSanta.xPos, y: SecondSanta.yPos})
      }
      distance--
    }
  })
  return SecondSanta.visitedTwice[0].x + SecondSanta.visitedTwice[0].y
}

console.log(`Part 1 Answer: Easter Bunny HQ is ${part1()} blocks away.`)
console.log(`Part 2 Answer: Easter Bunny HQ is really ${part2()} blocks away.`)