output_description: Print the minimum possible value of S_{max} - S_{min}.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      H W
attempt: #!/usr/bin/env python3
  # %% for atcoder uniittest use
  import sys
  
  input = lambda: sys.stdin.readline().rstrip()
  
  
  def pin(type=int):
      return map(type, input().split())
  
  
  def tupin(t=int):
      return tuple(pin(t))
  
  
  # %%code
  def resolve():
      H, W = pin()
  
      if H % 3 == 0 or W % 3 == 0:
          print(0)
          return
      #
      ans = min(H, W)
      for i in range(1, H):
          yoko = W * i
          a = W // 2 * (H - i)
          b = W * H - yoko - a
  
          t = max(yoko, a, b) - min(yoko, a, b)
          ans = min(t, ans)
  
      for j in range(1, W):
          yoko = H * j
          a = (H // 2) * (W - j)
          b = W * H - yoko - a
  
          t = max(yoko, a, b) - min(yoko, a, b)
          ans = min(t, ans)
      print(ans)
  
  
  # %%submit!
  resolve()
  
problem_description: Statement
  
  There is a bar of chocolate with a height of H blocks and a width of W blocks.
  Snuke is dividing this bar into exactly three pieces. He can only cut the bar
  along borders of blocks, and the shape of each piece must be a rectangle.
  
  Snuke is trying to divide the bar as evenly as possible. More specifically, he
  is trying to minimize S_{max} \- S_{min}, where S_{max} is the area (the
  number of blocks contained) of the largest piece, and S_{min} is the area of
  the smallest piece. Find the minimum possible value of S_{max} - S_{min}.
samples: [{"input": "3 5", "output": "0\n    \n\nIn the division below, S_{max} - S_{min} = 5 - 5 = 0.\n\n![2a9b2ef47b750c0b7ba3e865d4fb4203.png](https://atcoder.jp/img/arc074/2a9b2ef47b750c0b7ba3e865d4fb4203.png)\n\n* * *"}, {"input": "4 5", "output": "2\n    \n\nIn the division below, S_{max} - S_{min} = 8 - 6 = 2.\n\n![a42aae7aaaadc4640ac5cdf88684d913.png](https://atcoder.jp/img/arc074/a42aae7aaaadc4640ac5cdf88684d913.png)\n\n* * *"}, {"input": "5 5", "output": "4\n    \n\nIn the division below, S_{max} - S_{min} = 10 - 6 = 4.\n\n![eb0ad0cb3185b7ae418e21c472ff7f26.png](https://atcoder.jp/img/arc074/eb0ad0cb3185b7ae418e21c472ff7f26.png)\n\n* * *"}, {"input": "100000 2", "output": "1\n    \n\n* * *"}, {"input": "100000 100000", "output": "50000"}]