package main

import (
"fmt"
"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() {
    job := make(chan int, 10)
    result := make(chan int, 10)
    for w := 1; w <= 2; w++ {
        go worker(w, job, result)
    }
    for j := 1; j <= 9; j++ {
        job <- j
    }
    close(job)
    for a := 1; a <= 9; a++ {
        <-result
    }
}

worker 2 processing job 1
worker 1 processing job 2
worker 2 processing job 3
worker 1 processing job 4
worker 1 processing job 5
worker 2 processing job 6
worker 1 processing job 7
worker 2 processing job 8