comefrom: <doocs>1701.Average Waiting Time_1.py
code: def averageWaitingTime( customers: List[List[int]]) -> float:
      f = total_waiting_time = 0
      for arrival, time in customers:
          f = max(arrival, f) + time
          total_waiting_time += f - arrival
      return total_waiting_time / len(customers)
masked: def sample_funcname ( var_0 : List [ List [ int ] ] ) -> float :
      var_6 = var_4 = 0
      for var_7 , var_8 in var_0 :
          var_6 = max ( var_7 , var_6 ) + var_8
          var_4 += var_6 - var_7
      return var_4 / len ( var_0 )
  