advent2022/d11/main.js

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

const SCREEN_WIDTH = 40;
//const RELIEF = BigInt(3); // part 1
const RELIEF = BigInt(1); // part 2

function Monkey(monkeyPool, id) {
    this.pool = monkeyPool;
    this.id = id;
    this.items = [];
    this.operation = i => i;
    this.testValue = 0;
    this.ifTrue = null;
    this.ifFalse = null;
    this.inspect = 0;
}

Monkey.prototype.setOperation = function(line) {
    this.operator = line.substring(0, 1);
    let other = line.substring(2);
    this.operation = i => {
        let _other = other === 'old' ? i : BigInt(parseInt(other));
        switch (this.operator) {
            case '+':
                i = i + _other; break;
            case '*':
                i = i * _other; break;
        }
        return RELIEF == 1 ? (i % this.pool.maxDiv): Math.floor(Number(i / RELIEF));
    };
}

Monkey.prototype.run = function() {
    this.inspect += this.items.length;
    while (this.items.length) {
        let i = this.items.shift();
        i = this.operation(i);
        this.pool.monkeys[(i % this.testValue == 0) ? this.ifTrue : this.ifFalse].items.push(i);
    }
}

function MonkeyPool() {
    this.monkeys = [];
    this.maxDiv = 0;
}

MonkeyPool.prototype.push = function(i) {
    let m = new Monkey(this, i);
    this.monkeys[i] = m;
    return i;
}

MonkeyPool.prototype.round = function() {
    for (let i of this.monkeys)
        i.run();
}

MonkeyPool.prototype.debug = function() {
    for (let i of this.monkeys) console.log(i.id, i.inspect, i.items);
}

async function main() {
    let monkeys = new MonkeyPool();
    let currentMonkey = null;
    for await (let line of readline.createInterface({ input: process.stdin })) {
        line = line.trim();
        if (!line || !line.length)
            currentMonkey = null;
        else if (line.startsWith('Monkey '))
            currentMonkey = monkeys.push(parseInt(line.substr(7)));
        else if (line.startsWith('Starting items: '))
            monkeys.monkeys[currentMonkey].items = line.substring('Starting items: '.length).split(',').map(i => BigInt(parseInt(i.trim())));
        else if (line.startsWith('Operation: new = old '))
            monkeys.monkeys[currentMonkey].setOperation(line.substring('Operation: new = old '.length));
        else if (line.startsWith('Test: divisible by '))
            monkeys.monkeys[currentMonkey].testValue = BigInt(parseInt(line.substring('Test: divisible by'.length)));
        else if (line.startsWith('If true: throw to monkey '))
            monkeys.monkeys[currentMonkey].ifTrue = parseInt(line.substring('If true: throw to monkey '.length));
        else if (line.startsWith('If false: throw to monkey '))
            monkeys.monkeys[currentMonkey].ifFalse = parseInt(line.substring('If false: throw to monkey '.length));
    }
    monkeys.maxDiv = monkeys.monkeys.map(i => i.testValue).reduce((a, b) => a ? (a * b) : b);
    for (let i =0; i < 10000; ++i)
        monkeys.round();
    console.log(monkeys.monkeys.map(i => i.inspect).sort((a, b) => b -a).slice(0, 2).reduce((a, b) => a ? a*b : b));
    console.log(monkeys.monkeys.map(i => i.inspect));
};

(main());