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

This Sudoku Puzzle has 78 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Naked Pair, Naked Single, Locked Candidates Type 2 (Claiming), Naked Triple, Hidden Pair, undefined, Sue de Coq, Full House techniques.

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

Solution Steps:

  1. Row 4 / Column 4 → 1 (Hidden Single)
  2. Row 6 / Column 4 → 7 (Hidden Single)
  3. Locked Candidates Type 1 (Pointing): 5 in b3 => r4c8<>5
  4. Locked Candidates Type 1 (Pointing): 5 in b4 => r78c3<>5
  5. Locked Candidates Type 1 (Pointing): 6 in b4 => r79c3<>6
  6. Locked Candidates Type 1 (Pointing): 6 in b5 => r1c5<>6
  7. Locked Candidates Type 1 (Pointing): 9 in b8 => r13c4<>9
  8. Naked Pair: 2,8 in r4c17 => r4c358<>2, r4c89<>8
  9. Row 4 / Column 8 → 7 (Naked Single)
  10. Row 4 / Column 9 → 5 (Naked Single)
  11. Row 6 / Column 3 → 5 (Hidden Single)
  12. Row 6 / Column 5 → 6 (Hidden Single)
  13. Row 4 / Column 5 → 4 (Naked Single)
  14. Row 4 / Column 3 → 6 (Naked Single)
  15. Row 3 / Column 5 → 2 (Hidden Single)
  16. Locked Candidates Type 1 (Pointing): 2 in b5 => r5c38<>2
  17. Locked Candidates Type 1 (Pointing): 2 in b4 => r78c1<>2
  18. Locked Candidates Type 1 (Pointing): 3 in b5 => r5c8<>3
  19. Locked Candidates Type 1 (Pointing): 2 in b6 => r8c7<>2
  20. Locked Candidates Type 2 (Claiming): 3 in c5 => r1c46,r23c6,r3c4<>3
  21. Row 1 / Column 4 → 6 (Naked Single)
  22. Row 3 / Column 4 → 5 (Naked Single)
  23. Row 2 / Column 8 → 5 (Hidden Single)
  24. Locked Candidates Type 2 (Claiming): 8 in c9 => r79c8<>8
  25. Naked Triple: 1,3,9 in r2c157 => r2c36<>1, r2c3<>3, r2c3<>9
  26. Naked Triple: 4,7,9 in r13c2,r2c3 => r2c1,r3c3<>9, r3c3<>7
  27. Locked Candidates Type 1 (Pointing): 9 in b1 => r5789c2<>9
  28. Hidden Pair: 5,6 in r7c26 => r7c2<>7, r7c2<>8, r7c6<>2, r7c6<>3
  29. XY-Wing: 4/8/9 in r15c2,r5c8 => r1c8<>9
  30. W-Wing: 1/3 in r1c8,r2c1 connected by 3 in r12c5 => r2c7<>1
  31. Row 2 / Column 1 → 1 (Hidden Single)
  32. Row 3 / Column 3 → 3 (Naked Single)
  33. Sue de Coq: r7c123 - {2356789} (r7c48 - {239}, r89c2 - {5678}) => r8c3<>7, r7c9<>3, r7c9<>9
  34. XY-Chain: 3 3- r2c7 -9- r2c5 -3- r1c5 -9- r1c2 -4- r5c2 -8- r5c8 -9- r6c9 -3 => r6c7<>3
  35. Row 6 / Column 9 → 3 (Hidden Single)
  36. Locked Candidates Type 2 (Claiming): 9 in c9 => r79c8,r8c7<>9
  37. Naked Triple: 1,2,3 in r179c8 => r3c8<>1
  38. W-Wing: 3/9 in r2c7,r8c1 connected by 9 in r6c17 => r8c7<>3
  39. Row 8 / Column 7 → 1 (Naked Single)
  40. Row 2 / Column 7 → 3 (Hidden Single)
  41. Row 1 / Column 8 → 1 (Naked Single)
  42. Row 2 / Column 5 → 9 (Naked Single)
  43. Row 1 / Column 5 → 3 (Full House)
  44. Row 1 / Column 6 → 4 (Naked Single)
  45. Row 1 / Column 2 → 9 (Full House)
  46. Row 2 / Column 6 → 7 (Naked Single)
  47. Row 2 / Column 3 → 4 (Full House)
  48. Row 3 / Column 2 → 7 (Full House)
  49. Row 3 / Column 6 → 1 (Full House)
  50. Row 5 / Column 3 → 9 (Naked Single)
  51. Row 8 / Column 2 → 5 (Naked Single)
  52. Row 5 / Column 8 → 8 (Naked Single)
  53. Row 6 / Column 1 → 2 (Naked Single)
  54. Row 6 / Column 7 → 9 (Full House)
  55. Row 4 / Column 7 → 2 (Full House)
  56. Row 4 / Column 1 → 8 (Full House)
  57. Row 5 / Column 2 → 4 (Full House)
  58. Row 3 / Column 7 → 8 (Full House)
  59. Row 3 / Column 8 → 9 (Full House)
  60. Row 8 / Column 3 → 2 (Naked Single)
  61. Row 7 / Column 2 → 6 (Naked Single)
  62. Row 9 / Column 2 → 8 (Full House)
  63. Row 7 / Column 3 → 7 (Naked Single)
  64. Row 9 / Column 3 → 1 (Full House)
  65. Row 8 / Column 6 → 3 (Naked Single)
  66. Row 7 / Column 6 → 5 (Naked Single)
  67. Row 9 / Column 9 → 9 (Naked Single)
  68. Row 7 / Column 9 → 8 (Naked Single)
  69. Row 8 / Column 9 → 7 (Full House)
  70. Row 8 / Column 1 → 9 (Full House)
  71. Row 7 / Column 1 → 3 (Full House)
  72. Row 5 / Column 6 → 2 (Naked Single)
  73. Row 5 / Column 4 → 3 (Full House)
  74. Row 9 / Column 6 → 6 (Full House)
  75. Row 9 / Column 4 → 2 (Naked Single)
  76. Row 7 / Column 4 → 9 (Full House)
  77. Row 7 / Column 8 → 2 (Full House)
  78. Row 9 / Column 8 → 3 (Full House)
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