class Guard {
    constructor (id) {
        this.id = id;
        this.minutesAsleep = Array.from({ length: 60 }).map(() => 0);
        this.fellAsleepAt = null;
    }
  
    sleep (fellAsleepAt) {
        this.fellAsleepAt = fellAsleepAt;
    }
  
    awake (awokeAt) {
        for (let i = this.fellAsleepAt; i < awokeAt; i++) {
            this.minutesAsleep[i] += 1;
        }
    }
  
    get sleepiestMinute () {
        return this.minutesAsleep
            .map((value, index) => ({ index, value }))
            .sort((a, b) => b.value - a.value)[0].index;
        }
  }
  
const sleep = (input) => {
    const guards = {};
    const schedule = input
        .split('\n')
        .map((x) => x.trim())
        .sort()
        .map((x) => {
            const parts = x.match(/\[(\d{4})-(\d{2})-(\d{2}) (\d{2}):(\d{2})\] (.*)/);
    
            return {
            minute: +parts[5],
            message: parts[6],
            };
        });
  
    let currentGuard = null;
  
    for (let i = 0; i < schedule.length; i++) {
        const { message, minute } = schedule[i];
    
        if (/Guard/.test(message)) {
            const parts = message.match(/Guard #(\d+) begins shift/);
            const guardId = +parts[1];
            const guard = guards[guardId] ? guards[guardId] : new Guard(guardId);
    
            currentGuard = guards[guardId] = guard;
        } else if (message === 'falls asleep') {
            currentGuard.sleep(minute);
        } else if (message === 'wakes up') {
            currentGuard.awake(minute);
        }
    }
  
    const sleepiestGuard = Object
        .keys(guards)
        .map((guardId) => guards[guardId])
        .sort((a, b) => b.minutesAsleep[b.sleepiestMinute] -
                        a.minutesAsleep[a.sleepiestMinute])[0];
  
    return sleepiestGuard.id * sleepiestGuard.sleepiestMinute;
};

const fs = require('fs');
console.log(sleep(fs.readFileSync("input.txt").toString()));