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

This Sudoku Puzzle has 86 steps and it is solved using Finned Swordfish, Naked Single, Locked Candidates Type 1 (Pointing), Discontinuous Nice Loop, Grouped Discontinuous Nice Loop, undefined, Hidden Single, AIC, Sue de Coq, Skyscraper, Full House, Naked Triple techniques.

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

Solution Steps:

  1. Finned Swordfish: 6 r167 c235 fr1c1 => r3c23<>6
  2. Row 3 / Column 2 → 1 (Naked Single)
  3. Locked Candidates Type 1 (Pointing): 6 in b1 => r1c5<>6
  4. Discontinuous Nice Loop: 7 r7c8 -7- r7c2 =7= r8c1 =1= r9c1 =8= r2c1 -8- r3c3 -9- r3c8 -7- r7c8 => r7c8<>7
  5. Grouped Discontinuous Nice Loop: 3 r2c6 -3- r2c1 -8- r3c3 -9- r3c8 -7- r2c79 =7= r2c6 => r2c6<>3
  6. W-Wing: 7/9 in r2c6,r3c8 connected by 9 in r23c3 => r2c79,r3c56<>7
  7. Row 2 / Column 6 → 7 (Hidden Single)
  8. AIC: 4 4- r1c2 =4= r2c3 =9= r3c3 =8= r3c7 -8- r2c9 -4 => r1c789,r2c3<>4
  9. Row 1 / Column 2 → 4 (Hidden Single)
  10. Row 1 / Column 1 → 6 (Hidden Single)
  11. Locked Candidates Type 1 (Pointing): 3 in b1 => r2c4<>3
  12. Sue de Coq: r56c2 - {3567} (r9c2 - {56}, r45c1 - {237}) => r4c3<>2, r46c3<>3, r7c2<>6
  13. Locked Candidates Type 1 (Pointing): 2 in b4 => r89c1<>2
  14. AIC: 6 6- r3c6 -9- r2c4 -5- r8c4 =5= r8c3 -5- r9c2 -6- r7c3 =6= r7c5 -6 => r3c5,r89c6<>6
  15. Row 3 / Column 6 → 6 (Hidden Single)
  16. XYZ-Wing: 1/3/7 in r7c2,r8c16 => r8c3<>3
  17. Discontinuous Nice Loop: 3 r4c1 -3- r2c1 -8- r3c3 -9- r3c5 -2- r4c5 =2= r4c1 => r4c1<>3
  18. Discontinuous Nice Loop: 4 r4c8 -4- r4c3 -5- r5c2 =5= r5c8 =3= r4c8 => r4c8<>4
  19. Discontinuous Nice Loop: 4 r5c8 -4- r5c6 =4= r4c6 -4- r4c3 -5- r5c2 =5= r5c8 => r5c8<>4
  20. Row 9 / Column 8 → 4 (Hidden Single)
  21. Locked Candidates Type 1 (Pointing): 9 in b9 => r7c45<>9
  22. Sue de Coq: r12c4 - {2359} (r678c4 - {1358}, r3c5 - {29}) => r1c5<>2, r1c5<>9, r5c4<>3, r5c4<>8
  23. Discontinuous Nice Loop: 3/9 r5c6 =4= r5c9 -4- r2c9 =4= r2c7 =5= r2c4 -5- r8c4 =5= r8c3 -5- r4c3 -4- r4c6 =4= r5c6 => r5c6<>3, r5c6<>9
  24. Row 5 / Column 6 → 4 (Naked Single)
  25. Row 9 / Column 6 → 9 (Hidden Single)
  26. Discontinuous Nice Loop: 2/3/7/8 r5c5 =9= r5c4 =2= r1c4 -2- r1c9 -1- r9c9 =1= r9c1 =8= r2c1 -8- r3c3 -9- r3c5 =9= r5c5 => r5c5<>2, r5c5<>3, r5c5<>7, r5c5<>8
  27. Row 5 / Column 5 → 9 (Naked Single)
  28. Row 3 / Column 5 → 2 (Naked Single)
  29. Row 5 / Column 4 → 2 (Naked Single)
  30. Row 5 / Column 9 → 8 (Hidden Single)
  31. Row 2 / Column 9 → 4 (Naked Single)
  32. Row 4 / Column 1 → 2 (Hidden Single)
  33. Skyscraper: 7 in r5c1,r6c9 (connected by r8c19) => r5c8,r6c2<>7
  34. AIC: 7 7- r4c5 -3- r4c8 =3= r5c8 =5= r5c2 -5- r9c2 -6- r9c9 =6= r8c9 =7= r6c9 -7 => r4c78,r6c5<>7
  35. Row 4 / Column 5 → 7 (Hidden Single)
  36. Row 3 / Column 8 → 7 (Hidden Single)
  37. AIC: 8 8- r2c1 =8= r9c1 =1= r8c1 -1- r8c6 -3- r4c6 =3= r4c8 -3- r5c8 -5- r5c2 =5= r9c2 -5- r9c5 =5= r1c5 -5- r2c4 =5= r2c7 =8= r3c7 -8 => r2c7,r3c3<>8
  38. Row 3 / Column 3 → 9 (Naked Single)
  39. Row 3 / Column 7 → 8 (Full House)
  40. Discontinuous Nice Loop: 3 r6c4 -3- r6c2 -6- r9c2 -5- r9c5 =5= r1c5 =3= r1c4 -3- r6c4 => r6c4<>3
  41. XYZ-Wing: 1/3/8 in r67c4,r8c6 => r8c4<>1
  42. Naked Triple: 3,5,9 in r128c4 => r7c4<>3
  43. Discontinuous Nice Loop: 3 r7c5 -3- r6c5 =3= r6c2 =6= r6c3 -6- r7c3 =6= r7c5 => r7c5<>3
  44. Locked Candidates Type 1 (Pointing): 3 in b8 => r8c1<>3
  45. W-Wing: 7/1 in r6c9,r8c1 connected by 1 in r9c19 => r8c9<>7
  46. Row 6 / Column 9 → 7 (Hidden Single)
  47. 2-String Kite: 1 in r6c7,r8c6 (connected by r4c6,r6c4) => r8c7<>1
  48. XY-Chain: 5 5- r4c3 -4- r6c3 -6- r6c2 -3- r6c5 -8- r6c4 -1- r4c6 -3- r8c6 -1- r8c1 -7- r5c1 -3- r5c8 -5 => r4c78,r5c2<>5
  49. Row 4 / Column 3 → 5 (Hidden Single)
  50. Row 5 / Column 8 → 5 (Hidden Single)
  51. Row 9 / Column 2 → 5 (Hidden Single)
  52. Row 8 / Column 4 → 5 (Hidden Single)
  53. Row 2 / Column 4 → 9 (Naked Single)
  54. Row 1 / Column 4 → 3 (Naked Single)
  55. Row 1 / Column 5 → 5 (Full House)
  56. Row 2 / Column 7 → 5 (Naked Single)
  57. Row 4 / Column 7 → 4 (Hidden Single)
  58. Row 6 / Column 7 → 1 (Naked Single)
  59. Row 4 / Column 8 → 3 (Full House)
  60. Row 4 / Column 6 → 1 (Full House)
  61. Row 8 / Column 6 → 3 (Full House)
  62. Row 6 / Column 4 → 8 (Naked Single)
  63. Row 6 / Column 5 → 3 (Full House)
  64. Row 7 / Column 4 → 1 (Full House)
  65. Row 6 / Column 2 → 6 (Naked Single)
  66. Row 6 / Column 3 → 4 (Full House)
  67. Row 7 / Column 8 → 9 (Naked Single)
  68. Row 1 / Column 8 → 1 (Full House)
  69. Row 7 / Column 7 → 7 (Naked Single)
  70. Row 1 / Column 9 → 2 (Naked Single)
  71. Row 1 / Column 7 → 9 (Full House)
  72. Row 8 / Column 7 → 2 (Full House)
  73. Row 7 / Column 2 → 3 (Naked Single)
  74. Row 5 / Column 2 → 7 (Full House)
  75. Row 5 / Column 1 → 3 (Full House)
  76. Row 8 / Column 3 → 6 (Naked Single)
  77. Row 2 / Column 1 → 8 (Naked Single)
  78. Row 2 / Column 3 → 3 (Full House)
  79. Row 7 / Column 3 → 8 (Naked Single)
  80. Row 7 / Column 5 → 6 (Full House)
  81. Row 9 / Column 3 → 2 (Full House)
  82. Row 9 / Column 5 → 8 (Full House)
  83. Row 8 / Column 9 → 1 (Naked Single)
  84. Row 8 / Column 1 → 7 (Full House)
  85. Row 9 / Column 1 → 1 (Full House)
  86. Row 9 / Column 9 → 6 (Full House)
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