play.go

for _, question := range quiz.questions {
		timer := time.NewTimer(time.Duration(quiz.timer.secondsPerQuestion) * time.Second)
		fmt.Printf("Problem #%d: %s = ", question.id, question.question)

		answerCh := make(chan string)
		go func() {
			var answer string
			fmt.Scanf("%s\n", &answer)
			answerCh <- answer
			close(answerCh)
		}()

		select {
		case <-timer.C:
			fmt.Println("Time limit exceed!")
		case answer := <-answerCh:
			if answer == question.answer {
				quiz.score++
			}
		}
	}