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  1. N = 9
  2. tmp =  [[0,0,0,2,0,0,0,6,3],
  3. 		[3,0,0,0,0,5,4,0,1],
  4. 		[0,0,1,0,0,3,9,8,0],
  5. 		[0,0,0,0,0,0,0,9,0],
  6. 		[0,0,0,5,3,8,0,0,0],
  7. 		[0,3,0,0,0,0,0,0,0],
  8. 		[0,2,6,3,0,0,5,0,0],
  9. 		[5,0,3,7,0,0,0,0,8],
  10. 		[4,7,0,0,0,1,0,0,0]]
  11. # solution: http://w...content-available-to-author-only...u.ws/hard-1-solution.htm
  12.  
  13. sud = [[int(x) for x in tmp[i]] for i in range(N)]
  14.  
  15. def check(x, y, val):
  16.     if val in [i for i in sud[y]]:                  ### check row x for val
  17.        return 1
  18.     if val in [sud[i][x] for i in range(N)]:        ### check column y for val
  19.        return 1
  20.     xbox = int(x/3) * 3
  21.     ybox = int(y/3) * 3
  22.     for i in range(xbox, xbox+3):
  23.         for j in range(ybox, ybox+3):
  24.             if val == sud[i][j]:                    ### check box for val
  25.                 return 1
  26.     return 0
  27.  
  28. def solve(x = 0, y = 0):
  29.     if x == N:
  30.         y += 1
  31.         x = 0
  32.         if y == N:
  33.             return 1
  34.     if sud[y][x] > 0:
  35.         return solve(x + 1, y)
  36.     for i in range(1, N+1):
  37.         if not check(x, y, i):
  38.             sud[y][x] = i
  39.             if solve(x + 1, y):
  40.                 print(sud)
  41.     sud[y][x] = 0
  42.     return 0
  43.  
  44. solve(0,0)
Success #stdin #stdout 0.04s 7848KB
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stdout 
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https://ideone.com/dhnRYs
language:
Python (cpython 2.7.16)
created:
11 years ago
visibility:
public

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