test 2 codes output with bash and test genrator

i have 2 codes: a.out, b.out and gen.out.

i'm sure that b.out works correct for small input.

and gen.out generate random tests.

i want to generate N tests.

test1.in test2.in ... testN.in

and pass them to a.out & b.out and diff output of them.

and if codes outputs were different echo the number of test.

how is it possible using bash?