puzzle11.js

    // http://adventofcode.com/2017/day/11

    import data from './data.json'

    const steps = data.split(',')

    const pairs = steps.map(s => {
      switch (s) {
        case 'n':
          return [2, 0]
        case 'ne':
          return [1, 1]
        case 'se':
          return [-1, 1]
        case 's':
          return [-2, 0]
        case 'sw':
          return [-1, -1]
        case 'nw':
          return [1, -1]
        default:
          throw Error(s)
      }
    })

    const [north, east] = pairs.reduce(
      (acc, p) => {
        return [acc[0] + p[0], acc[1] + p[1]]
      },
      [0, 0],
    )

    const [absNorth, absEast] = [Math.abs(north), Math.abs(east)]

    const stepDistance = absNorth > absEast ? (absNorth - absEast) / 2 + absEast : absEast

    console.log('RESULT: ', north, east, stepDistance)