The baby is due October 3!
We resolve to 0 if he's born exactly on the due date. Other examples:
October 7 = 4 (4 days late)
October 2 = -1 (1 day early)
We'll go by the date on the official birth certificate.
If the baby is born outside the provided range, the question resolves to the nearest number.
Clarification: The question says
We resolve to 0 if he's born exactly on the due date.
I've noticed that when resolving, I'll actually be forced to choose a range like 0-1 or 1-2. Therefore I will define 0-1 as October 3, I think that's most intuitive. You could think of it as the due date being October 3 midnight, and the range meaning 0.0 days (inclusive) to 1.0 days (exclusive).
Clarification: The question says
We resolve to 0 if he's born exactly on the due date.
I've noticed that when resolving, I'll actually be forced to choose a range like 0-1 or 1-2. Therefore I will define 0-1 as October 3, I think that's most intuitive. You could think of it as the due date being October 3 midnight, and the range meaning 0.0 days (inclusive) to 1.0 days (exclusive).