It really easy if u've done programming...It's mostly logic arithmetics and prime numbers stuffs which doesn't really have anything to do with high school mathematics (apart from combinatorics).
I am doing third year BIT and when I was in 1st year I had to do MATH135, and then later MATH237 (which is the equiv. of DMTH137). I managed to squeeze in MATH136 as well, but all those subjects were shithouse.
I did it with 2U Maths & gap year. Heh, nearly failed.