Advent-of-Code 2022-02

day03.js

function intersect(left, right){
    return new Set([...left].filter(x => right.has(x)));
}

function* chunked(arr, n) {
    for (let i = 0; i < arr.length; i += n) {
        yield arr.slice(i, i + n);
    }
}

async function solve1(input){
    let [seed, value] = [[], 0]

    for (const line of (await readFile(input, { encoding: 'utf8' })).split('\n')){
        if (!line) continue;
        seed.push([line, line.length / 2])
    }

    for (const [rs, len] of seed){
        let [char] = intersect(new Set(rs.split('').slice(0, len)), new Set(rs.split('').slice(len, len*2)));
        value += char == char.toLowerCase() ? char.charCodeAt() - 96 : char.charCodeAt() - 38;
    }

    return value;
}

async function solve2(input){
    let [seed, value] = [[], 0]

    const lines = (await readFile(input, { encoding: 'utf8' })).split('\n');
    for (const chunk of chunked(lines.slice(0, lines.length -2), 3)){
        seed.push([chunk])
    }

    for (const [rucksack] of seed){
        var [tail, head] = [rucksack.slice(1, rucksack.length), new Set(rucksack[0])];
        let [char] = tail.reduce((a, v) => intersect(a, new Set(v)), head);
        value += char == char.toLowerCase() ? char.charCodeAt() - 96 : char.charCodeAt() - 38;
    }

    return value;
}

day03.py

def solve_1(input_=None):
    seed, value = [], 0
    with open(locate(input_), "r") as fp:
        for line in (line for line in fp.readlines() if line != "\n"):
            seed.append([i for i in re.findall(r"\w+", line)][0])

    for rucksacks, length in ((r, len(r) // 2) for r in seed):
        char, = set(rucksacks[:length]).intersection(rucksacks[length:])
        value += ord(char) - 96 if char == char.lower() else ord(char) - 38

    return value


def solve_2(input_=None):
    seed, value, n = [], 0, 0
    with open(locate(input_), "r") as fp:
        for chunk in chunked((line for line in fp.readlines() if line != "\n"), 3):
            seed.append([i for i in re.findall(r"\w+", line)][0] for line in chunk)

    for rucksacks in seed:
        char, = set.intersection(*[set(r) for r in rucksacks])
        value += ord(char) - 96 if char == char.lower() else ord(char) - 38

    return value