I've started to code my own little engine recently and am now working on a perft function which simply sees how many moves there are. Trying to get correct results I searched online for the correct amount of possible positions after e.g. 4 moves. Now according to these sources:
https://youtu.be/6Y_FaQhqX2c?t=5m46s
It should be 197281 possible positions after 4 moves, and I can reach that in my code!
But switching a bit around in my code to get some optimization which seemingly shouldn't change anything, I get a different number: 197742 Now I would think that is wrong but I have found different sources again, claiming that is in fact correct:
https://youtu.be/Km024eldY1A?t=5m33s
So, which one is it? 197742 or 197281 possible positions after 4 moves? I was a bit uncertain whether this belongs here or on StackOverflow. I went with this one, I hope that's alright.
EDIT: apparently I can't post more than two links due to my low reputation I'll post the links in comments
Thanks in advance Folling