advent2022/d13/main.js

const fs = require('fs');
const readline = require('readline');

function compareArray(a, b) {
    for (let i =0; i < a.length; ++i) {
        let comp = compare(a[i], b[i]);
        if (comp !== 0) return comp;
    }
    return a.length === b.length ? 0 : -1;
}

function compare(a, b) {
    if (b === undefined) return 1;
    if (Array.isArray(a) || Array.isArray(b))
        return compareArray(Array.isArray(a) ? a : [a], Array.isArray(b) ? b : [b]);
    if (a < b) return -1;
    if (a > b) return 1;
    return 0;
}

async function main() {
    let allLines = [[[2]], [[6]]];
    let lines = [];
    let index = 1;
    let total = 0;
    for await (let line of readline.createInterface({ input: process.stdin })) {
        if (line.length) {
            const data = JSON.parse(line);
            lines.push(data);
            allLines.push(data);
        } else {
            if (compare(lines[0], lines[1]) > 0)
                total += index;
            ++index;
            lines = [];
        }
    }
    allLines = allLines.sort(compare);
    console.log("Part 1: ", total);
    console.log("Part 2: ", (allLines.findIndex(i => compare(i, [[2]]) === 0) +1) *
            (allLines.findIndex(i => compare(i, [[6]]) === 0) +1));
};

(main());