output_description: Print the number of ways to choose a pair of an even number and an odd number
  from the positive integers between 1 and K (inclusive).
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      K
attempt: from math import log2
  
  L = int(input())
  ans = []
  i = 1
  while True:
      if 2**i > L:
          last = i
          break
      ans.append([i, i + 1, 2 ** (i - 1)])
      ans.append([i, i + 1, 0])
      i += 1
  """for i in ans:
      print(i)
  print(last)"""
  num = 2 ** (last - 1)
  a = L - num
  while a > 0:
      ans.append([int(log2(a)) + 1, last, num])
      num += 2 ** (int(log2(a)))
      a = L - num
  for i in ans:
      print(*i)
  
problem_description: Statement
  
  Find the number of ways to choose a pair of an even number and an odd number
  from the positive integers between 1 and K (inclusive). The order does not
  matter.
samples: [{"input": "3", "output": "2\n    \n\nTwo pairs can be chosen: (2,1) and (2,3).\n\n* * *"}, {"input": "6", "output": "9\n    \n\n* * *"}, {"input": "11", "output": "30\n    \n\n* * *"}, {"input": "50", "output": "625"}]