求翻译：在最短时间内记忆100个无规律数字，观察黑板上的100个数字，然后依次背出来，不能有任何错误。我已经练习了4年，最短用时1分钟。所需设备是黑板.粉笔。这是很值得挑战的。是什么意思？

Memory 100 irregular figures within the shortest time, observe 100 numbers on the Blackboard, then back out without any errors. I have 4 years of practice, the shortest time 1 minute. Equipment required is Blackboard. chalk. This is well worth the challenge.