这个题设计的很巧妙，cool

Thanks Voile for your help! :-)

This is a difficult kata, but it's very helpful in improving logical skills.

Have a Chinese :P

I had from the Chinese Spanish translation: "This question is difficult but useful for the updating failure logic". :-) ..Thanks Steffen.

Google-Translation says: "This problem is difficult, but it is helpful to judge the logic of ascension"

Oh my God, I don`t speak Chinese yet. Perhaps a Chinese user may help me to translate your message.

这个题很难，不过对于提升逻辑的判断很有帮助