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

This Sudoku Puzzle has 69 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Naked Triple, Naked Single, Naked Pair, undefined, Skyscraper, Hidden Rectangle, Sue de Coq, Full House techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 2 / Column 2 → 4 (Hidden Single)
2. Row 6 / Column 2 → 1 (Hidden Single)
3. Row 5 / Column 7 → 4 (Hidden Single)
4. Row 2 / Column 3 → 5 (Hidden Single)
5. Row 3 / Column 7 → 5 (Hidden Single)
6. Row 8 / Column 2 → 5 (Hidden Single)
7. Row 1 / Column 3 → 7 (Hidden Single)
8. Locked Candidates Type 1 (Pointing): 1 in b3 => r79c9<>1
9. Naked Triple: 3,6,8 in r245c8 => r68c8<>3, r67c8<>8, r78c8<>6
10. Row 6 / Column 8 → 9 (Naked Single)
11. Locked Candidates Type 1 (Pointing): 3 in b9 => r6c7<>3
12. Row 6 / Column 6 → 3 (Hidden Single)
13. Naked Pair: 1,6 in r18c6 => r27c6<>6, r7c6<>1
14. Naked Triple: 1,6,9 in r1c679 => r1c1<>6, r1c1<>9, r1c5<>1
15. Row 3 / Column 1 → 9 (Hidden Single)
16. Locked Candidates Type 1 (Pointing): 6 in b1 => r3c49<>6
17. X-Wing: 2 c24 r34 => r3c35,r4c15<>2
18. Skyscraper: 8 in r3c9,r6c7 (connected by r36c4) => r45c9<>8
19. W-Wing: 9/6 in r1c7,r8c4 connected by 6 in r2c48 => r8c7<>9
20. Row 8 / Column 4 → 9 (Hidden Single)
21. W-Wing: 3/6 in r8c7,r9c2 connected by 6 in r8c6,r9c4 => r8c3,r9c7<>3
22. Row 8 / Column 7 → 3 (Hidden Single)
23. Hidden Rectangle: 6/9 in r1c79,r9c79 => r9c9<>6
24. Sue de Coq: r23c4 - {2678} (r6c4 - {78}, r1c56,r3c5 - {1236}) => r49c4<>7, r4c4<>8
25. XY-Chain: 6 6- r2c8 -8- r3c9 -1- r3c5 -3- r1c5 -2- r5c5 -5- r5c9 -6 => r1c9,r45c8<>6
26. Row 2 / Column 8 → 6 (Hidden Single)
27. Row 1 / Column 7 → 9 (Naked Single)
28. Row 1 / Column 9 → 1 (Naked Single)
29. Row 3 / Column 9 → 8 (Full House)
30. Row 1 / Column 6 → 6 (Naked Single)
31. Row 3 / Column 4 → 2 (Naked Single)
32. Row 8 / Column 6 → 1 (Naked Single)
33. Row 1 / Column 5 → 3 (Naked Single)
34. Row 1 / Column 1 → 2 (Full House)
35. Row 4 / Column 4 → 4 (Naked Single)
36. Row 8 / Column 8 → 2 (Naked Single)
37. Row 8 / Column 3 → 6 (Full House)
38. Row 3 / Column 5 → 1 (Naked Single)
39. Row 9 / Column 4 → 6 (Naked Single)
40. Row 7 / Column 8 → 1 (Naked Single)
41. Row 3 / Column 3 → 3 (Naked Single)
42. Row 3 / Column 2 → 6 (Full House)
43. Row 9 / Column 2 → 3 (Naked Single)
44. Row 4 / Column 2 → 2 (Full House)
45. Row 5 / Column 3 → 8 (Naked Single)
46. Row 5 / Column 8 → 3 (Naked Single)
47. Row 4 / Column 8 → 8 (Full House)
48. Row 7 / Column 3 → 2 (Naked Single)
49. Row 9 / Column 3 → 1 (Full House)
50. Row 5 / Column 1 → 6 (Naked Single)
51. Row 4 / Column 1 → 3 (Full House)
52. Row 6 / Column 7 → 7 (Naked Single)
53. Row 6 / Column 4 → 8 (Full House)
54. Row 2 / Column 4 → 7 (Full House)
55. Row 2 / Column 6 → 8 (Full House)
56. Row 5 / Column 9 → 5 (Naked Single)
57. Row 4 / Column 9 → 6 (Full House)
58. Row 5 / Column 5 → 2 (Full House)
59. Row 9 / Column 7 → 8 (Naked Single)
60. Row 7 / Column 7 → 6 (Full House)
61. Row 7 / Column 9 → 7 (Naked Single)
62. Row 9 / Column 9 → 9 (Full House)
63. Row 9 / Column 1 → 4 (Naked Single)
64. Row 7 / Column 1 → 8 (Full House)
65. Row 9 / Column 5 → 7 (Full House)
66. Row 7 / Column 6 → 5 (Naked Single)
67. Row 4 / Column 6 → 7 (Full House)
68. Row 4 / Column 5 → 5 (Full House)
69. Row 7 / Column 5 → 4 (Full House)