package main

import (
    "fmt"
    "sync"

    "github.com/vardius/worker-pool/v2"
)

func main() {
	var wg sync.WaitGroup

	poolSize := 1
	jobsAmount := 3
	workersAmount := 2

	// create new pool
	pool := workerpool.New(poolSize)
	out := make(chan int, jobsAmount)
	worker := func(i int) {
        defer wg.Done()
        out <- i
    }

	for i := 1; i <= workersAmount; i++ {
		if err := pool.AddWorker(worker); err != nil {
			panic(err)
		}
	}

	wg.Add(jobsAmount)

	for i := 0; i < jobsAmount; i++ {
		if err := pool.Delegate(i); err != nil {
			panic(err)
		}
	}

	go func() {
		// stop all workers after jobs are done
		wg.Wait()
		close(out)
		pool.Stop() // stop removes all workers from pool, to resume work add them again
	}()

	sum := 0
	for n := range out {
		sum += n
	}

	fmt.Println(sum)
	// Output:
	// 3
}