8
2
4
9
4
3
9
7
8
1
6
2
5
5
2
6
2
4
1
4
9
8
2
6
2
6
4
2
5
1
2
9
6
7
8
4
3
8
2
3
6

This Sudoku Puzzle has 58 steps and it is solved using Locked Candidates Type 1 (Pointing), Locked Candidates Type 2 (Claiming), Skyscraper, Discontinuous Nice Loop, Naked Single, AIC, Hidden Single, Naked Triple, undefined, Full House, Naked Pair techniques.

Naked Single Explanation
Hidden Single Explanation
Locked Candidates Explanation
Locked Candidates Explanation
Full House Explanation
Try To Solve This Puzzle

Solution Steps:

  1. Locked Candidates Type 1 (Pointing): 1 in b1 => r3c789<>1
  2. Locked Candidates Type 2 (Claiming): 1 in c8 => r4c7,r5c9<>1
  3. Skyscraper: 9 in r4c8,r6c2 (connected by r7c28) => r4c3,r6c79<>9
  4. Discontinuous Nice Loop: 3/7/9 r7c3 =6= r7c1 -6- r1c1 -7- r9c1 -5- r2c1 =5= r2c3 =6= r7c3 => r7c3<>3, r7c3<>7, r7c3<>9
  5. Row 7 / Column 3 → 6 (Naked Single)
  6. AIC: 8 8- r3c8 =8= r3c7 =4= r3c9 -4- r8c9 =4= r8c1 =8= r8c3 -8- r6c3 =8= r6c7 -8 => r3c7,r4c8<>8
  7. Row 3 / Column 8 → 8 (Hidden Single)
  8. Discontinuous Nice Loop: 3 r2c1 -3- r7c1 =3= r7c2 =9= r9c3 -9- r9c9 =9= r2c9 =6= r2c1 => r2c1<>3
  9. Naked Triple: 5,6,7 in r129c1 => r48c1<>5, r47c1<>7
  10. Discontinuous Nice Loop: 3 r3c3 -3- r2c3 -5- r2c1 =5= r9c1 -5- r8c2 -1- r3c2 =1= r3c3 => r3c3<>3
  11. Discontinuous Nice Loop: 3/5/7 r6c7 =8= r6c3 =9= r9c3 -9- r9c9 =9= r2c9 -9- r2c7 -3- r2c3 =3= r3c2 -3- r7c2 =3= r7c1 -3- r4c1 -8- r4c7 =8= r6c7 => r6c7<>3, r6c7<>5, r6c7<>7
  12. Row 6 / Column 7 → 8 (Naked Single)
  13. AIC: 7 7- r7c8 -9- r4c8 =9= r4c7 =5= r9c7 -5- r9c1 -7 => r7c2,r9c79<>7
  14. W-Wing: 9/3 in r2c7,r7c2 connected by 3 in r2c3,r3c2 => r7c7<>9
  15. XY-Chain: 3 3- r4c1 -8- r8c1 -4- r7c1 -3- r7c2 -9- r7c8 -7- r5c8 -1- r5c4 -3 => r4c4,r5c2<>3
  16. Row 4 / Column 4 → 1 (Naked Single)
  17. Row 5 / Column 4 → 3 (Full House)
  18. Row 5 / Column 8 → 1 (Hidden Single)
  19. Discontinuous Nice Loop: 3/5/7 r6c3 =9= r6c2 -9- r7c2 -3- r3c2 =3= r2c3 -3- r2c7 -9- r2c9 =9= r9c9 -9- r9c3 =9= r6c3 => r6c3<>3, r6c3<>5, r6c3<>7
  20. Row 6 / Column 3 → 9 (Naked Single)
  21. Row 7 / Column 2 → 9 (Hidden Single)
  22. Row 7 / Column 8 → 7 (Naked Single)
  23. Row 4 / Column 8 → 9 (Full House)
  24. Row 7 / Column 7 → 4 (Naked Single)
  25. Row 7 / Column 1 → 3 (Full House)
  26. Row 4 / Column 1 → 8 (Naked Single)
  27. Row 8 / Column 1 → 4 (Naked Single)
  28. Row 3 / Column 9 → 4 (Hidden Single)
  29. Row 8 / Column 3 → 8 (Hidden Single)
  30. X-Wing: 5 r58 c29 => r6c29,r9c9<>5
  31. Row 6 / Column 5 → 5 (Hidden Single)
  32. Row 4 / Column 5 → 7 (Full House)
  33. Locked Candidates Type 1 (Pointing): 7 in b4 => r3c2<>7
  34. Locked Candidates Type 1 (Pointing): 7 in b6 => r1c9<>7
  35. Naked Pair: 3,5 in r24c3 => r9c3<>5
  36. Skyscraper: 3 in r3c2,r4c3 (connected by r34c7) => r2c3,r6c2<>3
  37. Row 2 / Column 3 → 5 (Naked Single)
  38. Row 6 / Column 2 → 7 (Naked Single)
  39. Row 6 / Column 9 → 3 (Full House)
  40. Row 2 / Column 1 → 6 (Naked Single)
  41. Row 4 / Column 3 → 3 (Naked Single)
  42. Row 5 / Column 2 → 5 (Full House)
  43. Row 4 / Column 7 → 5 (Full House)
  44. Row 5 / Column 9 → 7 (Full House)
  45. Row 1 / Column 1 → 7 (Naked Single)
  46. Row 9 / Column 1 → 5 (Full House)
  47. Row 2 / Column 9 → 9 (Naked Single)
  48. Row 2 / Column 7 → 3 (Full House)
  49. Row 8 / Column 2 → 1 (Naked Single)
  50. Row 3 / Column 2 → 3 (Full House)
  51. Row 3 / Column 3 → 1 (Full House)
  52. Row 3 / Column 7 → 7 (Full House)
  53. Row 8 / Column 9 → 5 (Full House)
  54. Row 9 / Column 3 → 7 (Full House)
  55. Row 1 / Column 7 → 1 (Naked Single)
  56. Row 1 / Column 9 → 6 (Full House)
  57. Row 9 / Column 9 → 1 (Full House)
  58. Row 9 / Column 7 → 9 (Full House)
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