Discussion on: Advent of Code 2019 Solution Megathread - Day 13: Care Package

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This was much easier indeed!

Part One

The only thing I've given for granted is that the machine, on the first part, never overwrites a tile, but I was ready to track that down eventually. I'm reporting just the relevant parts in JavaScript:

const game = createProgramInstance(codes, 1);
let blocks = 0;
while (true) {
  const { value: x } = game.next();
  if (typeof x === 'undefined') {
    break;
  }
  game.next();
  const { value: draw } = game.next();
  if (draw === 2) {
    blocks++;
  }
}
console.log(blocks);

Part Two

I don't know if you noticed the hidden message in the text: "You do have crew quarters, but they won't fit in the machine." 😂
Anyway, after the initial confusion about "how to play this game?!", I realized this is just Arkanoid/Breakout! 😄 I just have to move the paddle left and right to reach the ball.
The only change I did to the main routing was to set a fixed input value instead of a stack of values (joystickPosition).

const game = createProgramInstance(codes, 1);
let score;
let ballX;
let paddleX;
while (true) {
  const { value: x } = game.next();
  if (typeof x === 'undefined') {
    break;
  }
  const { value: y } = game.next();
  const { value } = game.next();
  if (x === -1 && y === 0) {
    score = value;
  } else if (value === 3) {
    paddleX = x;
  } else if (value === 4) {
    ballX = x;
  }
  joystickPosition = Math.sign(ballX - paddleX);
}
console.log(score);

Get my input at my repo.