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

This Sudoku Puzzle has 67 steps and it is solved using Hidden Single, Naked Single, Full House, Locked Candidates Type 1 (Pointing), Hidden Rectangle, AIC, Discontinuous Nice Loop, Skyscraper, Naked Pair techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 1 / Column 5 → 3 (Hidden Single)
2. Row 5 / Column 3 → 8 (Hidden Single)
3. Row 8 / Column 2 → 3 (Hidden Single)
4. Row 6 / Column 2 → 6 (Naked Single)
5. Row 4 / Column 2 → 4 (Naked Single)
6. Row 5 / Column 1 → 7 (Naked Single)
7. Row 6 / Column 1 → 3 (Full House)
8. Row 8 / Column 6 → 4 (Hidden Single)
9. Row 4 / Column 7 → 3 (Hidden Single)
10. Row 2 / Column 8 → 6 (Hidden Single)
11. Row 7 / Column 9 → 3 (Hidden Single)
12. Row 5 / Column 7 → 6 (Hidden Single)
13. Row 7 / Column 8 → 1 (Hidden Single)
14. Row 3 / Column 7 → 1 (Hidden Single)
15. Row 9 / Column 5 → 1 (Hidden Single)
16. Row 5 / Column 8 → 4 (Hidden Single)
17. Row 9 / Column 9 → 4 (Hidden Single)
18. Row 9 / Column 1 → 6 (Naked Single)
19. Row 2 / Column 4 → 1 (Hidden Single)
20. Row 5 / Column 6 → 1 (Hidden Single)
21. Row 1 / Column 3 → 6 (Hidden Single)
22. Locked Candidates Type 1 (Pointing): 9 in b3 => r56c9<>9
23. Row 5 / Column 9 → 2 (Naked Single)
24. Row 5 / Column 5 → 9 (Full House)
25. Row 1 / Column 7 → 2 (Hidden Single)
26. Locked Candidates Type 1 (Pointing): 2 in b7 => r7c45<>2
27. Hidden Rectangle: 6/7 in r4c45,r7c45 => r4c4<>7
28. AIC: 4 4- r1c1 =4= r1c4 =7= r2c6 =2= r2c2 =9= r3c3 =4= r7c3 -4 => r3c3,r7c1<>4
29. Row 7 / Column 3 → 4 (Hidden Single)
30. Discontinuous Nice Loop: 5/7/8 r6c8 =9= r6c7 -9- r9c7 -7- r9c3 =7= r8c3 =5= r8c8 =9= r6c8 => r6c8<>5, r6c8<>7, r6c8<>8
31. Row 6 / Column 8 → 9 (Naked Single)
32. Skyscraper: 8 in r1c8,r3c5 (connected by r4c58) => r1c4,r3c9<>8
33. Naked Pair: 5,9 in r3c39 => r3c1<>5
34. Skyscraper: 5 in r3c9,r8c8 (connected by r38c3) => r1c8<>5
35. Locked Candidates Type 1 (Pointing): 5 in b3 => r6c9<>5
36. AIC: 7 7- r1c4 -4- r1c1 -5- r7c1 =5= r7c7 -5- r6c7 =5= r6c6 =2= r2c6 =7= r2c9 -7 => r1c89,r2c6<>7
37. Row 1 / Column 8 → 8 (Naked Single)
38. Row 2 / Column 6 → 2 (Naked Single)
39. Row 1 / Column 9 → 5 (Naked Single)
40. Row 2 / Column 2 → 9 (Naked Single)
41. Row 2 / Column 9 → 7 (Full House)
42. Row 3 / Column 9 → 9 (Full House)
43. Row 7 / Column 2 → 2 (Full House)
44. Row 6 / Column 9 → 8 (Full House)
45. Row 3 / Column 5 → 8 (Naked Single)
46. Row 1 / Column 1 → 4 (Naked Single)
47. Row 1 / Column 4 → 7 (Full House)
48. Row 3 / Column 4 → 4 (Full House)
49. Row 3 / Column 3 → 5 (Naked Single)
50. Row 3 / Column 1 → 2 (Full House)
51. Row 7 / Column 1 → 5 (Full House)
52. Row 6 / Column 4 → 2 (Naked Single)
53. Row 8 / Column 4 → 9 (Naked Single)
54. Row 7 / Column 4 → 6 (Naked Single)
55. Row 4 / Column 4 → 8 (Full House)
56. Row 8 / Column 3 → 7 (Naked Single)
57. Row 9 / Column 3 → 9 (Full House)
58. Row 9 / Column 7 → 7 (Full House)
59. Row 7 / Column 5 → 7 (Naked Single)
60. Row 8 / Column 5 → 2 (Full House)
61. Row 8 / Column 8 → 5 (Full House)
62. Row 7 / Column 7 → 9 (Full House)
63. Row 6 / Column 7 → 5 (Full House)
64. Row 4 / Column 5 → 6 (Full House)
65. Row 4 / Column 8 → 7 (Full House)
66. Row 6 / Column 6 → 7 (Full House)
67. Row 4 / Column 6 → 5 (Full House)