--description--

Given a snowboarder's starting stance and a rotation in degrees, determine their landing stance.

• A snowboarder's stance is either "Regular" or "Goofy".
• Trick rotations are multiples of 90 degrees. Positive indicates clockwise rotation, and negative indicate counter-clockwise rotation.
• The landing stance flips every 180 degrees of rotation.

For example, given "Regular" and 90, return "Regular". Given "Regular" and 180 degrees, return "Goofy".

--hints--

getLandingStance("Regular", 90) should return "Regular".

assert.equal(getLandingStance("Regular", 90), "Regular");

getLandingStance("Regular", 180) should return "Goofy".

assert.equal(getLandingStance("Regular", 180), "Goofy");

getLandingStance("Goofy", -270) should return "Regular".

assert.equal(getLandingStance("Goofy", -270), "Regular");

getLandingStance("Regular", 2340) should return "Goofy".

assert.equal(getLandingStance("Regular", 2340), "Goofy");

getLandingStance("Goofy", 2160) should return "Goofy".

assert.equal(getLandingStance("Goofy", 2160), "Goofy");

getLandingStance("Goofy", -540) should return "Regular".

assert.equal(getLandingStance("Goofy", -540), "Regular");

--seed--

--seed-contents--

function getLandingStance(startStance, rotation) {

  return startStance;
}

--solutions--

function getLandingStance(startStance, rotation) {
  const flips = Math.floor(Math.abs(rotation) / 180);
  if (flips % 2 === 0) {
    return startStance;
  } else {
    return startStance === "Regular" ? "Goofy" : "Regular";
  }
}