Quiz: Event-Driven Programming

In the countdown timer example given below, we want to allow multiple countdowns to run simultaneously without interfering with each other. Which approach achieves this?

const EventEmitter = require('events');

// Create an instance of EventEmitter
const countdown = new EventEmitter();

// Add listeners
countdown.on('tick', (time) => {
    console.log(`Time remaining: ${time} seconds`);
});

countdown.on('end', () => {
    console.log('Countdown complete!');
});

// Function to start the countdown
function startCountdown(seconds) {
    let remaining = seconds;

    const interval = setInterval(() => {
        if (remaining > 0) {
            countdown.emit('tick', remaining);
            remaining--;
        } else {
            clearInterval(interval);
            countdown.emit('end');
        }
    }, 1000);
}

// Start a 5-second countdown
startCountdown(5);