output_description: Print the answer without units. Your output will be accepted when its absolute
  or relative error from the correct value is at most 10^{-9}.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      A B H M
attempt: k = int(input())
  s = input()
  if len(s) > k:
      s = s[:k] + "..."
  print(s)
  
problem_description: Statement
  
  Consider an analog clock whose hour and minute hands are A and B centimeters
  long, respectively.
  
  An endpoint of the hour hand and an endpoint of the minute hand are fixed at
  the same point, around which each hand rotates clockwise at constant angular
  velocity. It takes the hour and minute hands 12 hours and 1 hour to make one
  full rotation, respectively.
  
  At 0 o'clock, the two hands overlap each other. H hours and M minutes later,
  what is the distance in centimeters between the unfixed endpoints of the
  hands?
samples: [{"input": "3 4 9 0", "output": "5.00000000000000000000\n    \n\nThe two hands will be in the positions shown in the figure below, so the\nanswer is 5 centimeters.\n\n![The clock at <var>9</var>\no'clock](https://img.atcoder.jp/ghi/when_a_nameless_star_falls_into_the_sky.png)\n\n* * *"}, {"input": "3 4 10 40", "output": "4.56425719433005567605\n    \n\nThe two hands will be in the positions shown in the figure below. Note that\neach hand always rotates at constant angular velocity.\n\n![The clock at\n<var>10:40</var>](https://img.atcoder.jp/ghi/when_flower_petals_flutter.png)"}]