package main

import (
	"fmt"
	"sync"
	"time"
)

func worker(id int, done <-chan struct{}, wg *sync.WaitGroup) {
	defer wg.Done()
	fmt.Printf("Worker %d starting...
", id)
	for {
		select {
		case <-done:
			fmt.Printf("Worker %d received shutdown signal, exiting.
", id)
			return
		case <-time.After(500 * time.Millisecond):
			fmt.Printf("Worker %d still working...
", id)
		}
	}
}

func main() {
	var wg sync.WaitGroup
	done := make(chan struct{})

	numWorkers := 3
	for i := 1; i <= numWorkers; i++ {
		wg.Add(1)
		go worker(i, done, &wg)
	}

	fmt.Println("Main: Workers started. Running for 3 seconds...")
	time.Sleep(3 * time.Second)

	fmt.Println("Main: Sending shutdown signal to all workers...")
	close(done) // Closing the channel broadcasts to all listeners

	wg.Wait()
	fmt.Println("Main: All workers shut down.")
}