You should declare the UserReady array somewhere. I would change your gets_playersnum to get_maxplayers. The reason for this is that a player can have a higher id than the current amount of players in the server (ie: he is one of only two players in the server but his id is 11), whereas it can't go higher than the max players. You should also set i to 1 instead of 0 then, because there is no player 0.
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