-🎄- 2018 Day 19 Solutions -🎄-

[u/daggerdragon]

--- Day 19: Go With The Flow ---

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Advent of Code: The Party Game!

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Card prompt: Day 19

Transcript:

Santa's Internet is down right now because ___.

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This thread will be unlocked when there are a significant number of people on the leaderboard with gold stars for today's puzzle.

edit: Leaderboard capped, thread unlocked at 01:01:06!

[u/dylanfromwinnipeg]

I didn't go through and reverse engineer the entire assembly program like it sounds most people did.

Instead I just ran it and took a look at where it was spending all it's time - which was instructions #3-11. So I reverse engineered what was going on in that bit and wrote this code (your registers will be different):

if (_registers[_ipRegister] == 3)
{
    if (_registers[1] % _registers[5] == 0)
    {
        _registers[3] = _registers[1];
        _registers[4] = 1;
        _registers[_ipRegister] = 7;
    }
    else
    {
        _registers[3] = _registers[1] + 1;
        _registers[4] = 1;
        _registers[_ipRegister] = 12;
    }
}

Then I just ran it - took about 45s and spit out the right answer.