PDA is used for recognizing CFL which is generated by CFG.

Logic:

For each ‘a’ push 1X

For each ‘b’ pop 1X

Implementation:

$M = (Q, Σ, Ґ, δ, q_0, z_(0 ), F )$

$Q = {q_0, q_1, q_f}$

$Σ = {a, b}$

$Ґ = {X, R}$

$ q_0 = …