05AB1E-CMC: Given an integer, check whether the lengths of the runs of equal adjacent digits follow a pattern like this:
[a, b, a, b-1, a, b-2, ..., a, 1, a (?)], where by
(?). Test cases:
Truthy: 12212, 355545525, 667777007778877997, Falsy: 123456789, 122232222332
I mean that the final a may appear or not, in either case giving truthy results (
Was posted in TNB, but I'd like to see how you'd do it in 05AB1E)