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

This Sudoku Puzzle has 85 steps and it is solved using Hidden Single, Locked Triple, Naked Single, Locked Candidates Type 1 (Pointing), Naked Pair, undefined, Finned Swordfish, Sue de Coq, Discontinuous Nice Loop, Grouped Discontinuous Nice Loop, Continuous Nice Loop, Full House, Empty Rectangle, Naked Triple, Hidden Triple, Swordfish, Skyscraper, Uniqueness Test 1 techniques.

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

Solution Steps:

  1. Row 8 / Column 1 → 3 (Hidden Single)
  2. Row 7 / Column 9 → 9 (Hidden Single)
  3. Locked Triple: 2,4,9 in r5c456 => r46c5,r5c128,r6c6<>2, r5c128,r6c6<>4, r4c5,r5c12<>9
  4. Row 5 / Column 1 → 5 (Naked Single)
  5. Locked Candidates Type 1 (Pointing): 3 in b3 => r4c8<>3
  6. Locked Candidates Type 1 (Pointing): 4 in b7 => r46c2<>4
  7. Naked Pair: 2,9 in r1c2,r2c1 => r2c3,r3c2<>2, r2c3,r3c2<>9
  8. 2-String Kite: 6 in r5c2,r8c7 (connected by r4c7,r5c8) => r8c2<>6
  9. Finned Swordfish: 8 r357 c248 fr3c5 => r2c4<>8
  10. Sue de Coq: r46c7 - {4568} (r23c7 - {459}, r5c8 - {68}) => r4c8<>6, r8c7<>4, r8c7<>5
  11. Discontinuous Nice Loop: 2/3 r1c4 =7= r1c6 =9= r1c2 =2= r2c1 -2- r7c1 -7- r7c4 =7= r1c4 => r1c4<>2, r1c4<>3
  12. Row 1 / Column 4 → 7 (Naked Single)
  13. Discontinuous Nice Loop: 6 r9c2 -6- r5c2 -8- r5c8 =8= r6c7 =5= r6c9 -5- r8c9 -4- r8c2 =4= r9c2 => r9c2<>6
  14. Grouped Discontinuous Nice Loop: 4 r2c9 -4- r8c9 =4= r89c8 -4- r4c8 -2- r13c8 =2= r2c9 => r2c9<>4
  15. XY-Wing: 5/8/2 in r2c39,r6c3 => r6c9<>2
  16. Locked Candidates Type 1 (Pointing): 2 in b6 => r4c123<>2
  17. XY-Chain: 2 2- r1c2 -9- r2c1 -2- r2c9 -5- r2c3 -8- r6c3 -2 => r6c2<>2
  18. Continuous Nice Loop: 4/5/6 8= r6c7 =5= r6c9 -5- r8c9 -4- r8c2 =4= r9c2 =9= r9c3 -9- r4c3 -6- r4c7 =6= r8c7 =8= r6c7 =5 => r6c7,r8c8<>4, r2c9,r9c2<>5, r4c2<>6
  19. Row 2 / Column 9 → 2 (Naked Single)
  20. Row 1 / Column 8 → 3 (Naked Single)
  21. Row 2 / Column 1 → 9 (Naked Single)
  22. Row 1 / Column 2 → 2 (Naked Single)
  23. Row 1 / Column 6 → 9 (Full House)
  24. Row 4 / Column 8 → 2 (Hidden Single)
  25. Row 3 / Column 7 → 9 (Hidden Single)
  26. Row 5 / Column 5 → 9 (Hidden Single)
  27. Empty Rectangle: 5 in b9 (r3c28) => r8c2<>5
  28. W-Wing: 8/5 in r3c2,r6c7 connected by 5 in r2c37 => r6c2<>8
  29. Naked Triple: 1,3,7 in r6c256 => r6c1<>7, r6c9<>3
  30. Row 4 / Column 9 → 3 (Hidden Single)
  31. Hidden Triple: 5,6,8 in r357c2 => r7c2<>7
  32. XYZ-Wing: 5/6/9 in r49c3,r7c2 => r8c3<>6
  33. Naked Triple: 2,5,8 in r268c3 => r9c3<>5
  34. Swordfish: 5 r379 c268 => r8c68<>5
  35. Skyscraper: 6 in r8c7,r9c3 (connected by r4c37) => r9c8<>6
  36. XY-Chain: 8 8- r7c4 -2- r7c1 -7- r4c1 -4- r4c7 -6- r8c7 -8 => r7c8,r8c5<>8
  37. Row 7 / Column 4 → 8 (Hidden Single)
  38. Naked Pair: 5,6 in r7c28 => r7c6<>5, r7c6<>6
  39. Row 9 / Column 6 → 5 (Hidden Single)
  40. X-Wing: 6 r57 c28 => r8c8<>6
  41. W-Wing: 1/4 in r2c4,r9c8 connected by 4 in r2c7,r3c8 => r9c4<>1
  42. Row 9 / Column 4 → 3 (Naked Single)
  43. Row 2 / Column 4 → 1 (Hidden Single)
  44. Uniqueness Test 1: 2/4 in r3c46,r5c46 => r3c6<>2, r3c6<>4
  45. Row 3 / Column 6 → 3 (Naked Single)
  46. Row 6 / Column 5 → 3 (Hidden Single)
  47. Skyscraper: 7 in r6c2,r7c1 (connected by r67c6) => r4c1,r8c2<>7
  48. Row 4 / Column 1 → 4 (Naked Single)
  49. Row 8 / Column 2 → 4 (Naked Single)
  50. Row 4 / Column 7 → 6 (Naked Single)
  51. Row 6 / Column 1 → 2 (Naked Single)
  52. Row 7 / Column 1 → 7 (Full House)
  53. Row 8 / Column 9 → 5 (Naked Single)
  54. Row 6 / Column 9 → 4 (Full House)
  55. Row 9 / Column 2 → 9 (Naked Single)
  56. Row 4 / Column 3 → 9 (Naked Single)
  57. Row 5 / Column 8 → 8 (Naked Single)
  58. Row 6 / Column 7 → 5 (Full House)
  59. Row 8 / Column 7 → 8 (Naked Single)
  60. Row 2 / Column 7 → 4 (Full House)
  61. Row 3 / Column 8 → 5 (Full House)
  62. Row 6 / Column 3 → 8 (Naked Single)
  63. Row 7 / Column 6 → 2 (Naked Single)
  64. Row 7 / Column 8 → 6 (Naked Single)
  65. Row 7 / Column 2 → 5 (Full House)
  66. Row 8 / Column 3 → 2 (Naked Single)
  67. Row 9 / Column 3 → 6 (Full House)
  68. Row 2 / Column 3 → 5 (Full House)
  69. Row 3 / Column 2 → 8 (Full House)
  70. Row 5 / Column 2 → 6 (Naked Single)
  71. Row 8 / Column 8 → 1 (Naked Single)
  72. Row 9 / Column 8 → 4 (Full House)
  73. Row 9 / Column 5 → 1 (Full House)
  74. Row 2 / Column 6 → 6 (Naked Single)
  75. Row 2 / Column 5 → 8 (Full House)
  76. Row 5 / Column 6 → 4 (Naked Single)
  77. Row 5 / Column 4 → 2 (Full House)
  78. Row 3 / Column 4 → 4 (Full House)
  79. Row 3 / Column 5 → 2 (Full House)
  80. Row 4 / Column 5 → 7 (Naked Single)
  81. Row 4 / Column 2 → 1 (Full House)
  82. Row 6 / Column 6 → 1 (Full House)
  83. Row 8 / Column 6 → 7 (Full House)
  84. Row 8 / Column 5 → 6 (Full House)
  85. Row 6 / Column 2 → 7 (Full House)
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