如何创建有序数的平方:数组中的数组、bingo卡片和循环验证码……

At risk of being downvoted, I'm posting what should be a very simple problem, but I'm having a hard time figuring out where I'm going wrong. Before you downvote, please realise I've stared at this for some time trying to see my error, and this is an (embarrassing) last resort.At risk of being downvoted, I'm posting what sh