User:Msiddalingaiah/NFA to CFG

The following context-free_grammar describes the same language as the regular expression (a|b)*abb:

$A_0\to a{A}_0|b{A}_0|a{A}_1$

$A_1\to b{A}_2$

$A_2\to b{A}_3$

$A_3\to ϵ$

From page 178 of Aho, Sethi, Ullman