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// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/

// See page 244.

// Countdown implements the countdown for a rocket launch.
package main

import (
    "fmt"
    "time"
)

//!+
func main() {
    fmt.Println("Commencing countdown.")
    tick := time.Tick(1 * time.Second)
    for countdown := 10; countdown > 0; countdown-- {
        fmt.Println(countdown)
        <-tick
    }
    launch()
}

//!-

func launch() {
    fmt.Println("Lift off!")
}