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

This Sudoku Puzzle has 81 steps and it is solved using Naked Single, Hidden Single, Locked Candidates Type 1 (Pointing), undefined, Locked Candidates Type 2 (Claiming), Finned Swordfish, AIC, Discontinuous Nice Loop, Naked Triple, Naked Pair, Continuous Nice Loop, Skyscraper, Locked Pair, Full House, Sue de Coq, Swordfish techniques.

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

Solution Steps:

  1. Row 9 / Column 4 → 1 (Naked Single)
  2. Row 4 / Column 1 → 9 (Hidden Single)
  3. Row 6 / Column 9 → 5 (Hidden Single)
  4. Row 4 / Column 3 → 8 (Hidden Single)
  5. Row 4 / Column 9 → 7 (Hidden Single)
  6. Row 2 / Column 1 → 8 (Hidden Single)
  7. Locked Candidates Type 1 (Pointing): 2 in b4 => r5c6<>2
  8. Locked Candidates Type 1 (Pointing): 7 in b8 => r7c12<>7
  9. Locked Candidates Type 1 (Pointing): 3 in b9 => r5c8<>3
  10. XY-Wing: 4/6/3 in r4c7,r5c48 => r4c5<>3
  11. Row 4 / Column 7 → 3 (Hidden Single)
  12. Locked Candidates Type 2 (Claiming): 4 in r4 => r5c6,r6c5<>4
  13. Finned Swordfish: 6 r268 c579 fr2c6 => r3c5<>6
  14. AIC: 2/4 2- r3c9 =2= r1c7 =1= r1c6 -1- r5c6 -6- r5c8 -4- r7c8 =4= r7c9 -4 => r7c9<>2, r3c9<>4
  15. Discontinuous Nice Loop: 6 r8c7 -6- r6c7 =6= r6c5 =1= r2c5 -1- r1c6 =1= r1c7 =2= r8c7 => r8c7<>6
  16. Naked Triple: 1,2,7 in r8c137 => r8c59<>2, r8c9<>1
  17. Naked Triple: 2,6,9 in r389c9 => r27c9<>6, r2c9<>9
  18. XYZ-Wing: 1/2/4 in r18c7,r2c9 => r2c7<>1
  19. Naked Pair: 4,6 in r26c7 => r1c7<>4
  20. Finned Swordfish: 1 r158 c167 fr5c2 => r6c1<>1
  21. XY-Chain: 1 1- r2c9 -4- r2c7 -6- r6c7 -4- r5c8 -6- r5c6 -1 => r2c6<>1
  22. Continuous Nice Loop: 3/4 6= r6c5 =1= r2c5 -1- r2c9 -4- r2c7 -6- r6c7 =6= r6c5 =1 => r6c5<>3, r13c8,r2c236<>4
  23. Row 5 / Column 4 → 3 (Hidden Single)
  24. Locked Candidates Type 1 (Pointing): 4 in b3 => r2c5<>4
  25. Skyscraper: 6 in r7c4,r8c9 (connected by r3c49) => r7c8,r8c5<>6
  26. Row 8 / Column 5 → 9 (Naked Single)
  27. Row 8 / Column 9 → 6 (Naked Single)
  28. 2-String Kite: 6 in r2c7,r5c6 (connected by r5c8,r6c7) => r2c6<>6
  29. Row 2 / Column 6 → 9 (Naked Single)
  30. Locked Pair: 3,5 in r2c23 => r2c5,r3c12<>3
  31. Row 3 / Column 5 → 3 (Hidden Single)
  32. Row 4 / Column 5 → 4 (Hidden Single)
  33. Row 4 / Column 6 → 2 (Full House)
  34. Row 9 / Column 6 → 5 (Naked Single)
  35. Row 7 / Column 5 → 2 (Hidden Single)
  36. 2-String Kite: 2 in r1c7,r9c2 (connected by r8c7,r9c9) => r1c2<>2
  37. Sue de Coq: r79c2 - {1235} (r2c2 - {35}, r8c13 - {127}) => r7c1<>1, r5c2<>5, r6c2<>3
  38. Swordfish: 1 r267 c259 => r5c2<>1
  39. Sue de Coq: r56c2 - {1247} (r279c2 - {1235}, r6c13 - {347}) => r5c3<>4, r3c2<>2
  40. Skyscraper: 2 in r3c1,r9c2 (connected by r39c9) => r8c1<>2
  41. X-Wing: 2 r18 c37 => r5c3<>2
  42. Row 5 / Column 3 → 5 (Naked Single)
  43. Row 2 / Column 3 → 3 (Naked Single)
  44. Row 2 / Column 2 → 5 (Naked Single)
  45. Row 7 / Column 1 → 5 (Hidden Single)
  46. Row 6 / Column 1 → 3 (Hidden Single)
  47. XY-Wing: 4/7/2 in r5c2,r68c3 => r9c2<>2
  48. Row 9 / Column 2 → 3 (Naked Single)
  49. Row 7 / Column 2 → 1 (Naked Single)
  50. Row 9 / Column 8 → 9 (Naked Single)
  51. Row 9 / Column 9 → 2 (Full House)
  52. Row 7 / Column 9 → 4 (Naked Single)
  53. Row 8 / Column 1 → 7 (Naked Single)
  54. Row 8 / Column 3 → 2 (Full House)
  55. Row 8 / Column 7 → 1 (Full House)
  56. Row 7 / Column 8 → 3 (Full House)
  57. Row 1 / Column 8 → 8 (Naked Single)
  58. Row 3 / Column 9 → 9 (Naked Single)
  59. Row 2 / Column 9 → 1 (Full House)
  60. Row 3 / Column 1 → 2 (Naked Single)
  61. Row 5 / Column 1 → 1 (Full House)
  62. Row 1 / Column 7 → 2 (Naked Single)
  63. Row 1 / Column 4 → 7 (Naked Single)
  64. Row 3 / Column 8 → 6 (Naked Single)
  65. Row 2 / Column 7 → 4 (Full House)
  66. Row 2 / Column 5 → 6 (Full House)
  67. Row 5 / Column 8 → 4 (Full House)
  68. Row 6 / Column 7 → 6 (Full House)
  69. Row 6 / Column 5 → 1 (Full House)
  70. Row 5 / Column 6 → 6 (Full House)
  71. Row 5 / Column 2 → 2 (Full House)
  72. Row 1 / Column 3 → 4 (Naked Single)
  73. Row 6 / Column 3 → 7 (Full House)
  74. Row 6 / Column 2 → 4 (Full House)
  75. Row 7 / Column 4 → 6 (Naked Single)
  76. Row 3 / Column 4 → 8 (Full House)
  77. Row 7 / Column 6 → 7 (Full House)
  78. Row 3 / Column 6 → 4 (Naked Single)
  79. Row 1 / Column 6 → 1 (Full House)
  80. Row 1 / Column 2 → 9 (Full House)
  81. Row 3 / Column 2 → 7 (Full House)
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