Advent of Code 2019 - Day 13

Note: This topic is to talk about Day 13 of the Advent of Code 2019.

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A+++++++ would solve again!!1

I used a few simple IO.ANSI calls to display every screen change. Very entertaining!

Day 13 Part 2

The ball can become invisible. How strange… At the very least, it happens with my input.

This was fun, and easier than I expected. Here’s the code:

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I made a video of the game being played:


The most entertaining day so far -> solution

This is also the first day I am using my package, intcode to process the program.

Here’s my take.

Got to my solutions very quickly, though it part 2 tricked me… I just looked at the score when I was asked for input. Though the program tells you the final score without waiting for any input…

My solution. Today was fun!

My solution

For part2 I made a printout as its running. Disable this to run faster :slight_smile:
Here is a screenshot:

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Today was the best! I ended up implementing the whole game in interactive mode with ncurses support (which I had never used before) and it freaking rules. Then I plugged an “AI” back in it to beat the game while I watch and get the final score.
I actually had a lot of fun with this one. Great job to the intcode computer too!


Just finished it. It was indeed really fun :slight_smile:
What kind of performance do you have? (when running headless). Mine takes about 12s to complete
My solution:

I had problem with part 2 in the morning. The paddle would miss the ball and the would be lost almost immediately. It turned out that I updated the joystick state both when the score was received and when the ball was painted. Removing the update when the score was received fixed the problem.

Since I was late with posting anyway, I decided to do some clean up. I rewrote part 1 to use the same play bot as part 2, and inspired by @aaronnamba’s use of IO.ANSI I added a mix task to show an animation of game being played. To run the animation, just type mix animate.

My solution.

Both parts finish in 0.3 seconds.

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Let’s go back to work then!

It’s 3.5s for part 2 on my office VM. Have no further data points for comparing.

Part 1 runtime is negligible.

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It’s worthy to mention that all puzzles don’t take the time processing time

Still my implementation is the slowest and don’t find any obvious improvement. I’m wondering if the process + message passing implementation for the Intcode machine is suboptimal :thinking:

My puzzle input is available in the linked repository, you coul test your implementation against my import to determine if it was my machine or your input that made the difference. I can’t test your input on my implementation on my machine before Monday though.

It’s actually what I did against your puzzle (my previous post wasn’t clear).
It took 6sec on your puzzle whereas my puzzle took 12seconds.

But I’m still looking for optimization … nothing obvious yet

From a first glance over your code, pulling inputs one by one and handling them one by one seems costly.

I’m on a year’s end party of my office at the moment, but I’ll try to compare your input to mine on my home laptop tomorrow and post the result here.

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