Tha was not my issue, the problem is it asks the years to get the inhabitants "greater than or equal to p", I mistaken when I read it and when setting up I put a equal sign on the loop, it can't be equal there or it'll fail, because it'll loop more than it should.

Read until the end of the problem description

by logic it goes 1 extra, the weird thing is that it was still giving the right numbers at the end

I was getting the same error, the problem was the "=" sign in the loop, just getting rid of it solved the issue.

I don't know exactly what the problem was. I was getting the error 'expected 51 equal to 50.' It took me a while to realize, after some tests, that it was a sign in the condition of my loop. The weird thing is that even with that I was getting all the same results while testing it. After removing it, every test passed.