is L = {w in {0,1}* | #0(w) = #1(w)} a regular language?
I've managed to prove it is context free, but this doesn't really help.
I've also saw a hint (here - prove that l={w ∈ {0, 1}*: n0(w) ≠ n1(w)} is a non regular language?) to look at the complementing language which is {w in {0,1}* | #0(w) != #1(w)}, but I didn't manage to prove it is not regular either (I guess if I have then it would mean L is not regular.
Please help (I would prefer an explanation than a hint, I think i'm missing something basic here)
Thanks