codewars-car-park-escape.js

function escape(carpark){
  let instructions = []
  const floors = carpark.length
  const cells = carpark[0].length
  
  let [posX, posY] = findOurPosition(carpark)
  while (posX != floors - 1 || posY != cells - 1) {
    const stairY = findStair(carpark[posX])

    const newInstructions = generateInstructions(carpark, posX, posY, stairY)
    
    instructions = instructions.concat(newInstructions)
    console.log(instructions, newInstructions)
    
    const [x, y] = calculateNewPosition(carpark, posX, posY, stairY)
    posX += x
    posY += y
  }
  
  return instructions
}

function findOurPosition(carpark) {
  for (let i=0; i < carpark.length; i++) {
    for (let j=0; j < carpark[i].length; j++) {
      if (carpark[i][j] === 2) return [i, j]
    }
  }
}

function findStair(floor) {
  for (let i=0; i < floor.length; i++) {
    if (floor[i] == 1) return i
  }
  
  return -1
}

function generateInstructions(carpark, posX, posY, stairY) {
  if (stairY == -1) { // no hay escalera, estamos en el piso de abajo
    const spaces = carpark[0].length - 1 - posY
    return [`R${spaces}`]
  } else {
    const spaces = stairY - posY
    const direction = spaces < 0 ? "L" : "R"
    const instructions = [direction + Math.abs(spaces)]
      
    const floorsDown = calculateFloorsDown(carpark, posX, stairY)
    instructions.push(`D${floorsDown}`)
    return instructions
  }
}

function calculateNewPosition(carpark, posX, posY, stairY) {
  let spaces = 0, floors = 0
  if (stairY == -1) { // no hay escalera, estamos en el piso de abajo
    spaces = carpark[0].length - 1 - posY
  } else {
    spaces = stairY - posY
    floors = calculateFloorsDown(carpark, posX, stairY)
  }
  
  return [floors, spaces]
}

function calculateFloorsDown(carpark, posX, stairY) {
  let floorsDown = 0
  for (let i=posX; i < carpark.length && carpark[i][stairY] == 1; i++) {
    floorsDown++
  }
  return floorsDown
}