timeout.go

ans := make(chan int)
go input(ans)

rnd := rand.New(rand.NewSource(time.Now().UnixNano()))
count := 0
for i:= 1; i <= 10; i++ {
	n := rnd.Intn(100)
	m := rnd.Intn(100)
	fmt.Printf("%2d : %2d + %2d = ", i, n, m)
	select {
	case nm := <-ans:
		if nm == n+m {
			fmt.Println(">> correct!")
			count++
		} else {
			fmt.Println(">> wrong!!")
		}
	case <-time.After(5 * time.Second):
		fmt.Println()
		fmt.Println(">> timed out")
	}
}

fmt.Println("-----------------")
fmt.Println("correct:", count)