$S -> AB$
$A -> aA / epsilon$
$B ->aBb / epsilon$
What is the class of language generated by the above grammar ?
I think that it generates $a^* a^n b^n | n>=0$ so it should be regular as regular is concatenated with DCFL which is able generate epsilon. But the answer is CFL .
I think that answer would be CFL if n would have been greater than equal to 1 and not 0
Can someone please point out my mistake ?