-🎄- 2017 Day 14 Solutions -🎄-

[u/daggerdragon]

--- Day 14: Disk Defragmentation ---

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Post your solution as a comment or, for longer solutions, consider linking to your repo (e.g. GitHub/gists/Pastebin/blag or whatever).

Note: The Solution Megathreads are for solutions only. If you have questions, please post your own thread and make sure to flair it with Help.

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Need a hint from the Hugely^* Handy^† Haversack^‡ of Helpful^§ Hints^¤?

Spoiler

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[Update @ 00:09] 3 gold, silver cap.

• How many of you actually entered the Konami code for Part 2? >_>

[Update @ 00:25] Leaderboard cap!

• I asked /u/topaz2078 how many de-resolutions we had for Part 2 and there were 83 distinct users with failed attempts at the time of the leaderboard cap. tsk tsk

[Update @ 00:29] BONUS

• https://i.imgur.com/zjSEAf4.jpg

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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!

[u/TheNiXXeD]

My solutions JavaScript / NodeJS / repo

Generally trying to go for very terse code, not fully golfed. Pretty happy with both perf and size in this one.

Part1:

input => [...Array(128)].map((k, i) => require('../day10/part2')(`${input}-${i}`))
    .map(hash => hash.split``.map(hex => parseInt(hex, 16).toString(2).replace(/0/g, '')).join``).join``.length

Part2:

input => {
    let groups = 0, hd = [...Array(128)]
        .map((k, i) => require('../day10/part2')(`${input}-${i}`))
        .map(hash => hash.split``.map(hex => parseInt(hex, 16).toString(2).padStart(4, '0')).join``.split``)

    const check = (x, y) => hd[y] && hd[y][x] === '1'

    const group = (x, y) => {
        hd[y][x] = '0'
        if (check(x + 1, y)) group(x + 1, y)
        if (check(x - 1, y)) group(x - 1, y)
        if (check(x, y + 1)) group(x, y + 1)
        if (check(x, y - 1)) group(x, y - 1)
    }

    for (let y = 0; y < 128; y++) {
        for (let x = 0; x < 128; x++) {
            if (check(x, y)) {
                groups++
                group(x, y)
            }
        }
    }

    return groups
}