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: H, W = map(int, input().split())
  s = (H * W) / 3
  counth = 0
  while counth < s:
      counth += W
  if abs(counth - s) > abs(counth - s - W):
      counth -= W
  Mhs = counth
  counth = counth // W
  H1 = H - counth
  ls = [Mhs, H1 * (W // 2), H * W - Mhs - H1 * (W // 2)]
  # print(ls)
  ansh = [max(ls) - min(ls)]
  ls = [Mhs, W * (H1 // 2), H * W - Mhs - W * (H1 // 2)]
  # print(ls)
  ansh += [max(ls) - min(ls)]
  ansh = min(ansh)
  countw = 0
  while countw < s:
      countw += H
  if abs(countw - s) > abs(countw - s - H):
      countw -= H
  Mws = countw
  countw = countw // H
  W1 = W - countw
  ls = [Mws, W1 * (H // 2), H * W - Mws - W1 * (H // 2)]
  # print(ls)
  answ = [max(ls) - min(ls)]
  ls = [Mws, H * (W1 // 2), H * W - H * (W1 // 2) - Mws]
  answ += [max(ls) - min(ls)]
  # print(ls)
  answ = min(answ)
  print(min(ansh, answ))
  
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"}]