package main

import (
    "fmt"
    "os"
    "strconv"
)

func fibonacci(c, quit chan int) {
    x, y := 0, 1
    for {
        select {
        case c <- x:
            x, y = y, x + y
        case <- quit:
            return
        }
    }
}

func main() {
    count := 10
    if len(os.Args) > 1 {
        var err error
        if count, err = strconv.Atoi(os.Args[1]); err != nil {
            fmt.Fprintln(os.Stderr, os.Args[1], "is not an int!")
            os.Exit(1)
        }
    }
    c := make(chan int)
    quit := make(chan int)
    go func(count int) {
        for i := 0; i < count; i++ {
            fmt.Println(<-c)
        }
        quit <- 0
    }(count)
    fibonacci(c, quit)
}