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

This Sudoku Puzzle has 75 steps and it is solved using Hidden Single, Locked Pair, Naked Single, Locked Candidates Type 1 (Pointing), Finned Swordfish, undefined, Empty Rectangle, Discontinuous Nice Loop, Naked Pair, Uniqueness Test 1, Sue de Coq, Grouped AIC, Full House techniques.

Try To Solve This Puzzle

Solution Steps:

  1. Row 3 / Column 8 → 6 (Hidden Single)
  2. Locked Pair: 3,7 in r12c9 => r1c8,r2c7,r467c9<>3, r1c8,r2c7,r4678c9<>7
  3. Row 6 / Column 9 → 6 (Naked Single)
  4. Row 4 / Column 9 → 4 (Naked Single)
  5. Row 7 / Column 7 → 6 (Hidden Single)
  6. Row 2 / Column 3 → 4 (Hidden Single)
  7. Row 5 / Column 2 → 4 (Hidden Single)
  8. Row 7 / Column 1 → 4 (Hidden Single)
  9. Row 2 / Column 1 → 9 (Hidden Single)
  10. Row 9 / Column 8 → 4 (Hidden Single)
  11. Row 5 / Column 5 → 6 (Hidden Single)
  12. Row 4 / Column 2 → 6 (Hidden Single)
  13. Row 6 / Column 2 → 5 (Hidden Single)
  14. Row 6 / Column 3 → 9 (Hidden Single)
  15. Row 8 / Column 9 → 9 (Hidden Single)
  16. Row 7 / Column 9 → 1 (Naked Single)
  17. Locked Candidates Type 1 (Pointing): 7 in b5 => r13c6<>7
  18. Finned Swordfish: 8 r159 c467 fr5c8 => r46c7<>8
  19. Locked Candidates Type 1 (Pointing): 8 in b6 => r8c8<>8
  20. XY-Chain: 2 2- r1c8 -5- r8c8 -7- r8c1 -1- r8c3 -2 => r1c3<>2
  21. Row 8 / Column 3 → 2 (Hidden Single)
  22. Empty Rectangle: 1 in b4 (r8c15) => r4c5<>1
  23. Discontinuous Nice Loop: 3 r2c5 -3- r2c9 =3= r1c9 -3- r1c3 =3= r3c1 =7= r8c1 -7- r8c8 -5- r8c7 =5= r2c7 =2= r2c5 => r2c5<>3
  24. Naked Pair: 2,5 in r2c57 => r2c4<>5
  25. Uniqueness Test 1: 3/7 in r1c49,r2c49 => r1c4<>3, r1c4<>7
  26. Discontinuous Nice Loop: 7 r3c2 -7- r3c1 =7= r8c1 -7- r8c8 -5- r1c8 -2- r1c2 =2= r3c2 => r3c2<>7
  27. Sue de Coq: r1c23 - {1237} (r1c9 - {37}, r3c2 - {12}) => r3c1<>1, r1c6<>3
  28. Discontinuous Nice Loop: 1 r6c6 -1- r6c5 =1= r8c5 =8= r8c7 -8- r9c7 -3- r4c7 -7- r4c6 =7= r6c6 => r6c6<>1
  29. X-Wing: 1 r68 c15 => r4c1<>1
  30. Discontinuous Nice Loop: 7 r6c7 -7- r6c6 =7= r4c6 =5= r4c5 -5- r2c5 -2- r2c7 =2= r6c7 => r6c7<>7
  31. Discontinuous Nice Loop: 3 r7c6 -3- r7c8 =3= r9c7 -3- r6c7 -2- r2c7 =2= r2c5 -2- r7c5 =2= r7c6 => r7c6<>3
  32. Discontinuous Nice Loop: 5 r7c6 -5- r7c4 =5= r1c4 -5- r2c5 -2- r7c5 =2= r7c6 => r7c6<>5
  33. Grouped AIC: 2 2- r2c5 =2= r2c7 -2- r6c7 -3- r5c8 =3= r5c46 -3- r46c5 =3= r7c5 =2= r7c6 -2 => r13c6,r7c5<>2
  34. Row 3 / Column 2 → 2 (Hidden Single)
  35. Row 7 / Column 6 → 2 (Hidden Single)
  36. Row 2 / Column 5 → 2 (Hidden Single)
  37. Row 2 / Column 7 → 5 (Naked Single)
  38. Row 1 / Column 8 → 2 (Naked Single)
  39. Row 6 / Column 7 → 2 (Hidden Single)
  40. Locked Candidates Type 1 (Pointing): 1 in b1 => r1c46<>1
  41. W-Wing: 3/1 in r1c3,r3c6 connected by 1 in r4c36 => r3c1<>3
  42. Row 3 / Column 1 → 7 (Naked Single)
  43. Row 1 / Column 2 → 1 (Naked Single)
  44. Row 1 / Column 3 → 3 (Full House)
  45. Row 4 / Column 3 → 1 (Full House)
  46. Row 8 / Column 1 → 1 (Naked Single)
  47. Row 9 / Column 2 → 9 (Naked Single)
  48. Row 7 / Column 2 → 7 (Full House)
  49. Row 1 / Column 9 → 7 (Naked Single)
  50. Row 2 / Column 9 → 3 (Full House)
  51. Row 2 / Column 4 → 7 (Full House)
  52. Row 6 / Column 5 → 1 (Hidden Single)
  53. Row 7 / Column 4 → 9 (Hidden Single)
  54. Row 5 / Column 6 → 9 (Hidden Single)
  55. Row 1 / Column 4 → 5 (Hidden Single)
  56. Row 1 / Column 6 → 8 (Full House)
  57. Row 4 / Column 6 → 5 (Hidden Single)
  58. Row 4 / Column 7 → 7 (Hidden Single)
  59. Row 8 / Column 7 → 8 (Naked Single)
  60. Row 9 / Column 7 → 3 (Full House)
  61. Row 8 / Column 5 → 5 (Naked Single)
  62. Row 8 / Column 8 → 7 (Full House)
  63. Row 7 / Column 8 → 5 (Full House)
  64. Row 7 / Column 5 → 3 (Full House)
  65. Row 4 / Column 5 → 8 (Full House)
  66. Row 4 / Column 1 → 3 (Full House)
  67. Row 6 / Column 1 → 8 (Full House)
  68. Row 9 / Column 6 → 1 (Naked Single)
  69. Row 9 / Column 4 → 8 (Full House)
  70. Row 5 / Column 4 → 3 (Naked Single)
  71. Row 3 / Column 4 → 1 (Full House)
  72. Row 3 / Column 6 → 3 (Full House)
  73. Row 5 / Column 8 → 8 (Full House)
  74. Row 6 / Column 8 → 3 (Full House)
  75. Row 6 / Column 6 → 7 (Full House)
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