Last Friday morning (the 14th) it was unseasonably cold in Atlanta. On the way to work I noticed my car’s display giving the following temperature readings: 28, 30, 32, 34, 36 – all in Fahrenheit. It somehow knew to avoid the odd numbers.
But in the evening of the same day it read 39, 41, and 43. Now it knew how to avoid the even numbers.
I watched a little more closely for a while – on a trip on Sunday morning it read 46, and then 48. On Monday morning, 50, 52, and 54. Even again.
A puzzle for readers: what’s going on? (I know the answer.)
God plays dice 
For some reason the answer immediately jumped out at me, like within 5 seconds. I bet that as a programmer I’ve run into the exact same issue (I will not spoil it for others) and it stuck.
Assuming the answer is as given below, why does a programmer need it?
It’s measuring in integer degrees C, converting to F and rounding.