DH Key exchange attack: bad choice of g
I have solved the question by carrying out the Pohlig-Hellman attack for the smaller prime factors and finding that $b \equiv 3 \mod 11$ and $b \equiv 6 \mod 19$, then finding all the integers $&lt; 400$ satisfying this and testing them. The answer is $b=234$.

I am still interested in if anyone has a solution which usesthe order of $g$ though.