text: from common import get_input
  
  
  def get_result():
      # O(n) time and space
      timestamp, buses = get_input()
      buses = [int(b) for b in buses if b != "x"]
  
      best_departure = best_bus = None
      for bus in buses:
          rest = timestamp % bus
          prev_departure = timestamp - rest
          next_departure = prev_departure + bus
          if best_departure is None or next_departure < best_departure:
              best_departure = next_departure
              best_bus = bus
      
      return (best_departure - timestamp) * best_bus
  
  
  if __name__ == "__main__":
      print(get_result())
  