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This Sudoku Puzzle has 55 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Skyscraper, Empty Rectangle, Hidden Rectangle, Discontinuous Nice Loop, Naked Single, undefined, Full House, Naked Pair, Uniqueness Test 4 techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 6 / Column 7 → 8 (Hidden Single)
2. Locked Candidates Type 1 (Pointing): 9 in b3 => r1c123456<>9
3. Locked Candidates Type 1 (Pointing): 9 in b1 => r45678c1<>9
4. Skyscraper: 9 in r5c6,r6c3 (connected by r8c36) => r5c2,r6c45<>9
5. Empty Rectangle: 9 in b9 (r58c6) => r5c7<>9
6. Empty Rectangle: 9 in b6 (r68c3) => r8c8<>9
7. Hidden Rectangle: 1/2 in r1c46,r8c46 => r8c4<>1
8. Discontinuous Nice Loop: 4/9 r7c2 =6= r7c1 =1= r8c1 =5= r8c3 -5- r1c3 -6- r1c2 =6= r7c2 => r7c2<>4, r7c2<>9
9. Row 7 / Column 2 → 6 (Naked Single)
10. XY-Chain: 9 9- r6c3 -6- r1c3 -5- r1c2 -7- r3c1 -9- r2c1 -8- r2c4 -9- r9c4 -4- r9c2 -9 => r4c2,r8c3<>9
11. Row 8 / Column 3 → 5 (Naked Single)
12. Row 1 / Column 3 → 6 (Naked Single)
13. Row 6 / Column 3 → 9 (Full House)
14. Row 9 / Column 2 → 9 (Hidden Single)
15. Row 9 / Column 4 → 4 (Full House)
16. Row 6 / Column 1 → 6 (Hidden Single)
17. Locked Candidates Type 1 (Pointing): 9 in b6 => r1c8<>9
18. Locked Candidates Type 1 (Pointing): 4 in b7 => r45c1<>4
19. Naked Pair: 3,4 in r5c7,r6c9 => r45c8<>3, r45c8<>4
20. Row 4 / Column 2 → 4 (Hidden Single)
21. W-Wing: 4/3 in r1c8,r6c9 connected by 3 in r8c89 => r1c9<>4
22. Uniqueness Test 4: 5/7 in r1c12,r5c12 => r15c1<>7
23. XY-Chain: 4 4- r5c7 -3- r5c1 -5- r1c1 -8- r2c1 -9- r3c1 -7- r3c5 -9- r7c5 -1- r6c5 -4 => r5c5,r6c9<>4
24. Row 6 / Column 9 → 3 (Naked Single)
25. Row 1 / Column 9 → 9 (Naked Single)
26. Row 8 / Column 9 → 4 (Full House)
27. Row 5 / Column 7 → 4 (Naked Single)
28. Row 6 / Column 4 → 1 (Naked Single)
29. Row 6 / Column 5 → 4 (Full House)
30. Row 7 / Column 7 → 9 (Naked Single)
31. Row 8 / Column 8 → 3 (Full House)
32. Row 1 / Column 7 → 3 (Full House)
33. Row 1 / Column 8 → 4 (Full House)
34. Row 8 / Column 1 → 1 (Naked Single)
35. Row 7 / Column 1 → 4 (Full House)
36. Row 7 / Column 5 → 1 (Full House)
37. Row 5 / Column 1 → 3 (Hidden Single)
38. Row 4 / Column 1 → 7 (Naked Single)
39. Row 5 / Column 2 → 5 (Full House)
40. Row 1 / Column 2 → 7 (Full House)
41. Row 3 / Column 1 → 9 (Naked Single)
42. Row 3 / Column 5 → 7 (Full House)
43. Row 4 / Column 8 → 9 (Naked Single)
44. Row 4 / Column 4 → 3 (Full House)
45. Row 5 / Column 8 → 7 (Full House)
46. Row 1 / Column 5 → 2 (Naked Single)
47. Row 5 / Column 5 → 9 (Full House)
48. Row 5 / Column 6 → 2 (Full House)
49. Row 2 / Column 1 → 8 (Naked Single)
50. Row 1 / Column 1 → 5 (Full House)
51. Row 2 / Column 4 → 9 (Full House)
52. Row 1 / Column 4 → 8 (Naked Single)
53. Row 1 / Column 6 → 1 (Full House)
54. Row 8 / Column 6 → 9 (Full House)
55. Row 8 / Column 4 → 2 (Full House)