I agree. Both user is also submitted same code to my problem CRCLE_E1. Here is the screenshot:
By the way, this picture isn't spoiler because it only show <25% of overall code. and only contain meaningless information.
It's hard to clean all cheater. Because currently there are more than 200K users on SPOJ. I just consider the big cheater with high points (on main SPOJ site), rapidly solve many problem just in few minutes. If I found cheater with match that criteria, I'll definitely report here to be banned by admin.