[Crayder]

pawn Код:

forward RACtime(); public RACtime()
{
    new bool:unwanted[CAR_AMOUNT];
    for(new player=0; player<MAX_PLAYERS; player++) if(IsPlayerInAnyVehicle(player))
        unwanted[GetPlayerVehicleID(player)]=true;
    for(new car = 1; car <= 420; car++) if(!unwanted[car] || IsTrailerAttachedToVehicle(player)) 
        SetVehicleToRespawn(car);
}

I don't know wtf CAR_AMOUNT is, so this might not work... But if it's just a MAX_VEHICLES type of thing, then the following code will work perfect for 0.3.7:

pawn Код:

forward RACtime(); public RACtime()
{
    new bool:unwanted[CAR_AMOUNT];
    for(new player=0; player < GetPlayerPoolSize(); player++) if(IsPlayerInAnyVehicle(player))
        unwanted[GetPlayerVehicleID(player)]=true;
    for(new car; car < GetVehiclePoolSize(); car++) if(!unwanted[car] || IsTrailerAttachedToVehicle(player)) 
        SetVehicleToRespawn(car);
}