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: import math
  H,W=map(int,input().split())
  if H%3==0 or W%3==0:
    print(0)
    exit(0)
  S=[0]*3
  s=H*import math
  H,W=map(int,input().split())
  if H%3==0 or W%3==0:
    print(0)
    exit(0)
  S=[0]*3
  s=H*W/3
  w0=math.ceil(s/H)
  h0=math.ceil(s/W)
  
  S[0]=w0*H
  w1=W-W/3
  w0=math.ceil(s/H)
  h0=math.ceil(s/W)
  
  S[0]=w0*H
  w1=W-w0
  if w1%2==0 or H%2==0:
    S[1]=(H*w1)//2
    S[2]=(H*w1)//2
  else:
    s1=H*w1/2
    w10=math.ceil(s1/H)
    h10=math.ceil(s1/w1)
    S[2]=max((w1-w10)*H,(H-h10)*w1)
  ans=abs(S[0]-S[2])
  
  S[0]=W*h0
  h1=H-h0
  if h1%2==0 or W%2==0:
    S[1]=(W*h1)//2
    S[2]=(W*h1)//2
  else:
    s1=h1*W/2
    w11=math.ceil(s1/h1)
    h11=math.ceil(s1/W)
    S[2]=max((W-w11)*h1,(h1-h11)*W)
  ans=min(ans,abs(S[0]-S[2]))
  
  
  S=[0]*3
  s=H*W/3
  w0=math.floor(s/H)
  h0=math.floor(s/W)
  
  S[0]=w0*H
  w1=W-w0
  if w1%2==0 or H%2==0:
    S[1]=(H*w1)//2
    S[2]=(H*w1)//2
  else:
    s1=H*w1/2
    w10=math.floor(s1/H)
    h10=math.floor(s1/w1)
    S[2]=max((w1-w10)*H,(H-h10)*w1)
  ans=min(ans,abs(S[0]-S[2]))
  
  S[0]=W*h0
  h1=H-h0
  if h1%2==0 or W%2==0:
    S[1]=(W*h1)//2
    S[2]=(W*h1)//2
  else:
    s1=h1*W/2
    w11=math.floor(s1/h1)
    h11=math.floor(s1/W)
    S[2]=max((W-w11)*h1,(h1-h11)*W)
  ans=min(ans,abs(S[0]-S[2]))
  
  print(ans)
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"}]