Concurrency programming example: test user reflexes

reflexes.go

package main

import (
	"bufio"
	"fmt"
	"math/rand"
	"os"
	"time"
)

func init() {
	rand.Seed(time.Now().UnixNano())
}

func main() {
	channel := make(chan time.Time)
	
	go func() {
		reader := bufio.NewReader(os.Stdin)
		reader.ReadString('\n')
		channel <- time.Now()
	}()
	
	time.Sleep(time.Second * time.Duration(rand.Intn(11)))
	paused := time.Now()
	fmt.Println("GO!")
	
	entered := <- channel
	if paused.Sub(entered) > 0 {
		fmt.Println("FAIL")
	} else {
		fmt.Printf("%v\n", time.Since(entered))
	}
}

you have an error in line 32; should be "entered.Sub(paused)"