producer, consumer

main.go

package main

import "sync"

func producer(ch chan int, i int) {
	ch <- i * 2
}

func consumer(ch chan int, wg *sync.WaitGroup) {
	defer wg.Done()

	for i := range ch {
		println(i)
		wg.Done()
	}
}

func main() {
	var wg sync.WaitGroup
	ch := make(chan int)

	for i := 0; i < 10; i++ {
		wg.Add(1)
		go producer(ch, i)
	}

	go consumer(ch, &wg)

	wg.Wait()

}