On: Mod and remainder are not the same

[antoineMoPa]

Yeah I remember this notation completely messing up with my brain back in my discrete math class.

[0x7f800000 → antoineMoPa]

Clock arithmetic.

Modulo 4: a clock with only four evenly-spaced marks on it.

17 is congruent to 1 (modulo 4) means:

Starting at the top of the clock, go clockwise one mark.

Starting at the top of the clock, go clockwise seventeen marks.

You'll end up at the same position.

That's congruence.