package main

import (
	"fmt"
	"runtime"
	"time"
)

func worker(id int, jobs <-chan int, results chan<- int) {
	for j := range jobs {
		fmt.Println("worker ", id, "processing job ", j)
		time.Sleep(time.Second)
		results <- j * 2
	}
}

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())
	jobs := make(chan int, 100)
	results := make(chan int, 100)

	for j := 1; j <= 11; j++ {
		jobs <- j
	}
	close(jobs)

	for w := 1; w <= 4; w++ {
		go worker(w, jobs, results)
	}

	res := 0
	for j := 1; j <= 11; j++ {
		res += <-results
	}
	fmt.Println("results ", res)
}