I wrote my first non-BASIC program ever on a PDP-10 or 11 and as I remember, it was one of those numberical programming for Engineers classes where we had to figure out why, when using floating-points vs integer math, that 2 != 2.0 (because 2.0 was actually 2.0000000000001 of course)

The funny thing was...no one told me the secret and I musta spent 5 long hours pulling out my hair.

If I remember right, one of the RAs running the computer center finally had pity on me and showed me what was going on...

I'm not really sure I can call them the "good ole days of programming", but that was how things were done back then.