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

This Sudoku Puzzle has 82 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), undefined, Skyscraper, AIC, Discontinuous Nice Loop, Naked Single, Locked Candidates Type 2 (Claiming), Full House techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 6 / Column 7 → 2 (Hidden Single)
2. Row 6 / Column 3 → 7 (Hidden Single)
3. Row 9 / Column 2 → 7 (Hidden Single)
4. Row 7 / Column 5 → 7 (Hidden Single)
5. Row 7 / Column 1 → 9 (Hidden Single)
6. Row 3 / Column 7 → 7 (Hidden Single)
7. Row 5 / Column 9 → 7 (Hidden Single)
8. Row 9 / Column 4 → 2 (Hidden Single)
9. Row 3 / Column 5 → 2 (Hidden Single)
10. Row 7 / Column 4 → 8 (Hidden Single)
11. Locked Candidates Type 1 (Pointing): 3 in b3 => r89c9<>3
12. Locked Candidates Type 1 (Pointing): 6 in b8 => r13c6<>6
13. X-Wing: 9 r26 c59 => r1c9<>9
14. Skyscraper: 3 in r5c2,r9c1 (connected by r59c6) => r4c1,r78c2<>3
15. Skyscraper: 8 in r8c2,r9c8 (connected by r3c28) => r8c9,r9c1<>8
16. AIC: 1 1- r7c2 -6- r6c2 -4- r5c2 -3- r5c6 =3= r4c5 -3- r8c5 -1 => r7c6,r8c12<>1
17. Skyscraper: 1 in r7c2,r9c6 (connected by r3c26) => r9c1<>1
18. Row 7 / Column 2 → 1 (Hidden Single)
19. 2-String Kite: 1 in r4c8,r8c5 (connected by r8c9,r9c8) => r4c5<>1
20. Locked Candidates Type 1 (Pointing): 1 in b5 => r6c9<>1
21. Discontinuous Nice Loop: 4/5 r6c4 =1= r6c5 =9= r2c5 -9- r1c6 -5- r3c6 -1- r3c4 =1= r6c4 => r6c4<>4, r6c4<>5
22. Row 6 / Column 4 → 1 (Naked Single)
23. Locked Candidates Type 1 (Pointing): 5 in b5 => r5c8<>5
24. Discontinuous Nice Loop: 6 r1c2 -6- r2c3 -8- r3c2 =8= r8c2 =2= r1c2 => r1c2<>6
25. Discontinuous Nice Loop: 8 r2c1 -8- r4c1 =8= r4c3 =3= r4c5 -3- r8c5 -1- r2c5 =1= r2c1 => r2c1<>8
26. Discontinuous Nice Loop: 4/6 r6c1 =5= r6c9 =9= r2c9 =8= r2c3 -8- r4c3 =8= r4c1 =5= r6c1 => r6c1<>4, r6c1<>6
27. Row 6 / Column 1 → 5 (Naked Single)
28. Discontinuous Nice Loop: 3 r1c2 -3- r5c2 -4- r5c8 -9- r1c8 =9= r2c9 =8= r2c3 -8- r3c2 =8= r8c2 =2= r1c2 => r1c2<>3
29. Discontinuous Nice Loop: 6 r2c3 -6- r2c7 -4- r7c7 =4= r7c8 -4- r5c8 -9- r1c8 =9= r2c9 =8= r2c3 => r2c3<>6
30. Row 2 / Column 3 → 8 (Naked Single)
31. Row 8 / Column 2 → 8 (Hidden Single)
32. Row 4 / Column 1 → 8 (Hidden Single)
33. Row 8 / Column 3 → 2 (Hidden Single)
34. Row 1 / Column 2 → 2 (Hidden Single)
35. Locked Candidates Type 1 (Pointing): 4 in b4 => r3c2<>4
36. Locked Candidates Type 1 (Pointing): 3 in b7 => r3c1<>3
37. Locked Candidates Type 1 (Pointing): 6 in b7 => r23c1<>6
38. Locked Candidates Type 2 (Claiming): 6 in r2 => r1c89,r3c89<>6
39. W-Wing: 9/4 in r5c8,r6c5 connected by 4 in r56c2 => r5c6,r6c9<>9
40. Row 5 / Column 8 → 9 (Hidden Single)
41. Row 1 / Column 6 → 9 (Hidden Single)
42. Row 6 / Column 5 → 9 (Hidden Single)
43. Row 2 / Column 9 → 9 (Hidden Single)
44. Row 2 / Column 7 → 6 (Hidden Single)
45. W-Wing: 5/4 in r1c8,r4c7 connected by 4 in r7c78 => r4c8<>5
46. Locked Candidates Type 2 (Claiming): 5 in c8 => r13c9<>5
47. W-Wing: 4/3 in r1c9,r4c5 connected by 3 in r14c3 => r4c9<>4
48. W-Wing: 6/4 in r6c9,r7c8 connected by 4 in r47c7 => r4c8,r89c9<>6
49. Row 8 / Column 1 → 6 (Hidden Single)
50. Row 9 / Column 1 → 3 (Full House)
51. W-Wing: 4/3 in r4c5,r7c7 connected by 3 in r8c57 => r4c7<>4
52. Row 4 / Column 7 → 5 (Naked Single)
53. Row 8 / Column 7 → 3 (Naked Single)
54. Row 7 / Column 7 → 4 (Full House)
55. Row 8 / Column 5 → 1 (Naked Single)
56. Row 8 / Column 9 → 5 (Full House)
57. Row 7 / Column 8 → 6 (Naked Single)
58. Row 7 / Column 6 → 3 (Full House)
59. Row 9 / Column 6 → 6 (Full House)
60. Row 2 / Column 5 → 4 (Naked Single)
61. Row 2 / Column 1 → 1 (Full House)
62. Row 4 / Column 5 → 3 (Full House)
63. Row 3 / Column 1 → 4 (Full House)
64. Row 5 / Column 6 → 5 (Naked Single)
65. Row 3 / Column 6 → 1 (Full House)
66. Row 5 / Column 4 → 4 (Full House)
67. Row 5 / Column 2 → 3 (Full House)
68. Row 4 / Column 3 → 6 (Naked Single)
69. Row 1 / Column 3 → 3 (Full House)
70. Row 3 / Column 2 → 6 (Full House)
71. Row 6 / Column 2 → 4 (Full House)
72. Row 6 / Column 9 → 6 (Full House)
73. Row 4 / Column 9 → 1 (Naked Single)
74. Row 4 / Column 8 → 4 (Full House)
75. Row 1 / Column 9 → 4 (Naked Single)
76. Row 3 / Column 4 → 5 (Naked Single)
77. Row 1 / Column 4 → 6 (Full House)
78. Row 1 / Column 8 → 5 (Full House)
79. Row 9 / Column 9 → 8 (Naked Single)
80. Row 3 / Column 9 → 3 (Full House)
81. Row 3 / Column 8 → 8 (Full House)
82. Row 9 / Column 8 → 1 (Full House)