Let some finite array of integers is given initially.
There is a number k which is initially '0'.
In a move, a player will select a number from the array arr[i] and change k to gcd(k,arr[i]).
Also, the number chosen from the array(i.e a[i]) will be removed from that array.
A player who makes k=1 at any step loses. A player who cannot move also loses. 2 players are playing the game optimally.
When will the player who moves first wins the game?