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.

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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