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

This Sudoku Puzzle has 81 steps and it is solved using Hidden Single, Naked Single, Locked Pair, Locked Candidates Type 1 (Pointing), undefined, AIC, Hidden Pair, Naked Triple, Naked Pair, Skyscraper, Locked Candidates Type 2 (Claiming), Uniqueness Test 2, Uniqueness Test 4, Full House techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 3 / Column 2 → 1 (Hidden Single)
2. Row 1 / Column 9 → 8 (Hidden Single)
3. Row 6 / Column 4 → 1 (Hidden Single)
4. Row 8 / Column 8 → 2 (Hidden Single)
5. Row 4 / Column 4 → 8 (Hidden Single)
6. Row 4 / Column 8 → 5 (Naked Single)
7. Locked Pair: 5,9 in r8c46 => r7c56,r8c29,r9c5<>5, r7c56,r8c29,r9c5<>9
8. Row 7 / Column 6 → 4 (Naked Single)
9. Locked Candidates Type 1 (Pointing): 6 in b5 => r3c5<>6
10. Locked Candidates Type 1 (Pointing): 7 in b5 => r2c6<>7
11. 2-String Kite: 3 in r2c8,r8c2 (connected by r7c8,r8c9) => r2c2<>3
12. AIC: 3 3- r7c8 =3= r2c8 -3- r2c6 =3= r5c6 =2= r4c6 =7= r4c9 -7- r2c9 =7= r2c4 =6= r2c2 -6- r8c2 -3 => r7c23,r8c9<>3
13. Row 8 / Column 9 → 6 (Naked Single)
14. Row 8 / Column 2 → 3 (Naked Single)
15. XY-Chain: 9 9- r5c9 -1- r5c8 -8- r6c8 -4- r2c8 -3- r2c6 -5- r8c6 -9 => r5c6<>9
16. AIC: 4 4- r1c2 =4= r2c2 =6= r2c4 =7= r2c9 -7- r4c9 =7= r4c6 =2= r5c6 =3= r2c6 -3- r2c8 -4 => r1c7,r2c2<>4
17. Row 1 / Column 2 → 4 (Hidden Single)
18. Row 3 / Column 5 → 4 (Hidden Single)
19. AIC: 6 6- r2c2 -5- r2c6 -3- r2c8 -4- r6c8 =4= r6c7 =7= r4c9 -7- r2c9 =7= r2c4 =6= r3c4 -6 => r2c4,r3c13<>6
20. Row 2 / Column 2 → 6 (Hidden Single)
21. Row 3 / Column 4 → 6 (Hidden Single)
22. Row 4 / Column 5 → 6 (Hidden Single)
23. Hidden Pair: 6,7 in r7c13 => r7c13<>5, r7c1<>8, r7c3<>9
24. XY-Chain: 7 7- r2c4 -5- r2c6 -3- r2c8 -4- r6c8 -8- r5c8 -1- r5c9 -9- r4c9 -7 => r2c9<>7
25. Row 2 / Column 4 → 7 (Hidden Single)
26. AIC: 9 9- r4c2 -2- r4c6 =2= r5c6 =3= r2c6 -3- r2c8 =3= r7c8 =1= r5c8 -1- r5c9 -9 => r4c9,r5c3<>9
27. Row 4 / Column 9 → 7 (Naked Single)
28. Row 6 / Column 6 → 7 (Hidden Single)
29. Naked Triple: 3,4,5 in r2c89,r3c9 => r13c7<>5
30. Locked Candidates Type 1 (Pointing): 5 in b3 => r79c9<>5
31. XYZ-Wing: 1/3/9 in r57c9,r7c8 => r9c9<>1
32. Row 9 / Column 5 → 1 (Hidden Single)
33. Row 7 / Column 5 → 8 (Naked Single)
34. Naked Pair: 5,9 in r7c27 => r7c9<>9
35. Skyscraper: 9 in r5c9,r6c3 (connected by r9c39) => r6c7<>9
36. Locked Candidates Type 1 (Pointing): 9 in b6 => r5c5<>9
37. W-Wing: 5/9 in r6c5,r7c2 connected by 9 in r4c26 => r6c2<>5
38. Locked Candidates Type 2 (Claiming): 5 in c2 => r9c13<>5
39. Uniqueness Test 2: 2/7 in r1c17,r3c17 => r13c3,r5c1<>5
40. Uniqueness Test 4: 5/9 in r7c27,r9c27 => r9c27<>9
41. XY-Chain: 5 5- r2c6 -3- r2c8 -4- r6c8 -8- r6c2 -9- r6c5 -5 => r1c5,r5c6<>5
42. XY-Chain: 2 2- r4c2 -9- r7c2 -5- r7c7 -9- r5c7 -6- r6c7 -4- r6c8 -8- r6c2 -9- r6c5 -5- r5c5 -3- r5c6 -2 => r4c6,r5c13<>2
43. Row 4 / Column 6 → 9 (Naked Single)
44. Row 4 / Column 2 → 2 (Full House)
45. Row 6 / Column 5 → 5 (Naked Single)
46. Row 8 / Column 6 → 5 (Naked Single)
47. Row 8 / Column 4 → 9 (Full House)
48. Row 1 / Column 4 → 5 (Full House)
49. Row 5 / Column 5 → 3 (Naked Single)
50. Row 1 / Column 5 → 9 (Full House)
51. Row 2 / Column 6 → 3 (Full House)
52. Row 5 / Column 6 → 2 (Full House)
53. Row 2 / Column 8 → 4 (Naked Single)
54. Row 2 / Column 9 → 5 (Full House)
55. Row 6 / Column 8 → 8 (Naked Single)
56. Row 3 / Column 9 → 3 (Naked Single)
57. Row 5 / Column 8 → 1 (Naked Single)
58. Row 7 / Column 8 → 3 (Full House)
59. Row 6 / Column 2 → 9 (Naked Single)
60. Row 7 / Column 9 → 1 (Naked Single)
61. Row 5 / Column 9 → 9 (Naked Single)
62. Row 9 / Column 9 → 4 (Full House)
63. Row 6 / Column 3 → 6 (Naked Single)
64. Row 6 / Column 7 → 4 (Full House)
65. Row 5 / Column 7 → 6 (Full House)
66. Row 7 / Column 2 → 5 (Naked Single)
67. Row 9 / Column 2 → 8 (Full House)
68. Row 9 / Column 7 → 5 (Naked Single)
69. Row 7 / Column 7 → 9 (Full House)
70. Row 5 / Column 1 → 8 (Naked Single)
71. Row 5 / Column 3 → 5 (Full House)
72. Row 7 / Column 3 → 7 (Naked Single)
73. Row 7 / Column 1 → 6 (Full House)
74. Row 9 / Column 1 → 2 (Naked Single)
75. Row 9 / Column 3 → 9 (Full House)
76. Row 3 / Column 3 → 2 (Naked Single)
77. Row 1 / Column 3 → 3 (Full House)
78. Row 1 / Column 1 → 7 (Naked Single)
79. Row 1 / Column 7 → 2 (Full House)
80. Row 3 / Column 7 → 7 (Full House)
81. Row 3 / Column 1 → 5 (Full House)