SPOJ Classical – Hubulullu – HUBULLU

After duelling in quake (a multiplayer game), Airborne and Pagfloyd decide do test themselves out in another game called Hubulullu. The rules of the game are as follows:

N wooden pieces (marked with numbers 1 to N) are placed in a transparent bottle. On his turn the first player takes out some piece (numbered x) and all the pieces numbered by divisors of x that are present in the transparent bottle. The second player picks another number and removes it and its divisors as well. Play continues in an alternating fashion until all pieces have been removed from the bottle. The player who removes the last piece from the bottle wins the game.