func turnAround() {
  turnLeft()
  turnLeft()
}
func solveStair() {
  moveForward()
  collectGem()
}
solveStair()
turnAround()
moveForward()
solveStair()
turnAround()
moveForward()
turnLeft()
solveStair()
turnAround()
moveForward()
solveStair()
