output_description: Print the specified string (case-sensitive).
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      D
attempt: def f(level, x):
      if level == 0:
          return x
  
      if x in [1, 0]:
          return 0
      elif x == b[level][0]:
          return b[level][1]
      elif 2 <= x < b[level - 1][0] + 2:
          return f(level - 1, x - 1)
      elif x == b[level - 1][0] + 2:
          return b[level - 1][1] + 1
      elif b[level - 1][0] + 2 < x < b[level][0]:
          return b[level - 1][1] + 1 + f(level - 1, x - (b[level - 1][0] + 2))
  
  
  N, X = map(int, input().split())
  b = [[1, 1] for i in range(N + 1)]
  for i in range(1, N + 1):
      b[i][0] = b[i - 1][0] * 2 + 3
      b[i][1] = b[i - 1][1] * 2 + 1
  
  print(f(N, X))
  
problem_description: Statement
  
  In some other world, today is December D-th.
  
  Write a program that prints `Christmas` if D = 25, `Christmas Eve` if D = 24,
  `Christmas Eve Eve` if D = 23 and `Christmas Eve Eve Eve` if D = 22.
samples: [{"input": "25", "output": "Christmas\n    \n\n* * *"}, {"input": "22", "output": "Christmas Eve Eve Eve\n    \n\nBe sure to print spaces between the words."}]