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

This Sudoku Puzzle has 74 steps and it is solved using Hidden Single, Naked Single, Full House, Locked Candidates Type 1 (Pointing), Hidden Pair, Naked Pair, Turbot Fish, Uniqueness Test 1, Empty Rectangle, Hidden Rectangle, undefined, Skyscraper techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 2 / Column 7 → 8 (Hidden Single)
2. Row 4 / Column 4 → 8 (Hidden Single)
3. Row 6 / Column 1 → 8 (Hidden Single)
4. Row 1 / Column 7 → 9 (Hidden Single)
5. Row 3 / Column 4 → 9 (Hidden Single)
6. Row 8 / Column 9 → 8 (Hidden Single)
7. Row 8 / Column 8 → 9 (Hidden Single)
8. Row 8 / Column 2 → 1 (Hidden Single)
9. Row 6 / Column 2 → 3 (Naked Single)
10. Row 4 / Column 2 → 5 (Naked Single)
11. Row 5 / Column 2 → 9 (Naked Single)
12. Row 5 / Column 1 → 4 (Naked Single)
13. Row 5 / Column 3 → 1 (Full House)
14. Row 6 / Column 4 → 1 (Hidden Single)
15. Row 7 / Column 1 → 9 (Hidden Single)
16. Locked Candidates Type 1 (Pointing): 4 in b5 => r128c6<>4
17. Locked Candidates Type 1 (Pointing): 2 in b7 => r13c1<>2
18. Row 1 / Column 1 → 5 (Naked Single)
19. Hidden Pair: 1,5 in r9c89 => r9c8<>3, r9c89<>6, r9c9<>7
20. Row 4 / Column 8 → 3 (Hidden Single)
21. Row 5 / Column 6 → 3 (Hidden Single)
22. Row 5 / Column 5 → 5 (Hidden Single)
23. Row 2 / Column 6 → 5 (Hidden Single)
24. Naked Pair: 4,6 in r26c8 => r3c8<>4, r3c8<>6
25. Turbot Fish: 6 r2c8 =6= r6c8 -6- r6c6 =6= r5c4 => r2c4<>6
26. Uniqueness Test 1: 1/5 in r3c89,r9c89 => r3c9<>1, r3c9<>5
27. Row 3 / Column 8 → 5 (Hidden Single)
28. Row 9 / Column 8 → 1 (Naked Single)
29. Row 9 / Column 9 → 5 (Naked Single)
30. Row 3 / Column 5 → 1 (Hidden Single)
31. Row 1 / Column 9 → 1 (Hidden Single)
32. Row 1 / Column 6 → 2 (Hidden Single)
33. Row 2 / Column 2 → 2 (Hidden Single)
34. Locked Candidates Type 1 (Pointing): 6 in b2 => r79c5<>6
35. Empty Rectangle: 6 in b9 (r37c2) => r3c7<>6
36. Hidden Rectangle: 2/7 in r8c14,r9c14 => r9c4<>7
37. XY-Wing: 6/7/2 in r8c16,r9c4 => r8c4,r9c1<>2
38. Row 8 / Column 1 → 2 (Hidden Single)
39. Row 9 / Column 4 → 2 (Hidden Single)
40. Locked Candidates Type 1 (Pointing): 6 in b8 => r8c7<>6
41. W-Wing: 4/7 in r4c9,r8c7 connected by 7 in r48c6 => r7c9<>4
42. Locked Candidates Type 1 (Pointing): 4 in b9 => r3c7<>4
43. Row 3 / Column 7 → 2 (Naked Single)
44. Row 5 / Column 9 → 2 (Hidden Single)
45. Naked Pair: 6,7 in r7c29 => r7c37<>6, r7c57<>7
46. X-Wing: 6 c29 r37 => r3c3<>6
47. Skyscraper: 7 in r7c9,r8c6 (connected by r4c69) => r8c7<>7
48. Row 8 / Column 7 → 4 (Naked Single)
49. Row 7 / Column 7 → 3 (Naked Single)
50. Row 7 / Column 3 → 8 (Naked Single)
51. Row 7 / Column 5 → 4 (Naked Single)
52. Row 1 / Column 5 → 6 (Naked Single)
53. Row 1 / Column 3 → 4 (Full House)
54. Row 2 / Column 5 → 7 (Naked Single)
55. Row 2 / Column 4 → 4 (Full House)
56. Row 9 / Column 5 → 8 (Full House)
57. Row 2 / Column 8 → 6 (Full House)
58. Row 3 / Column 9 → 4 (Full House)
59. Row 6 / Column 8 → 4 (Full House)
60. Row 6 / Column 6 → 6 (Full House)
61. Row 3 / Column 3 → 3 (Naked Single)
62. Row 9 / Column 3 → 6 (Full House)
63. Row 4 / Column 9 → 7 (Naked Single)
64. Row 4 / Column 6 → 4 (Full House)
65. Row 5 / Column 4 → 7 (Full House)
66. Row 8 / Column 6 → 7 (Full House)
67. Row 5 / Column 7 → 6 (Full House)
68. Row 9 / Column 7 → 7 (Full House)
69. Row 7 / Column 9 → 6 (Full House)
70. Row 7 / Column 2 → 7 (Full House)
71. Row 8 / Column 4 → 6 (Full House)
72. Row 9 / Column 1 → 3 (Full House)
73. Row 3 / Column 1 → 7 (Full House)
74. Row 3 / Column 2 → 6 (Full House)