[SDraw]

PHP код:

stock GetValidVehiclesCount()
{
        new count;
        for(new x = 1; x <= MAX_VEHICLES; x++)
        {
            switch(GetVehicleModel(x))
            {
                case 400..611: count++;
                default: continue;
            }
        }
        return count;
} 


Also, there is no vehicle with id 0. Only from 1 to 2000.