Passaggi della soluzione:

1. Riga 5 / Colonna 2 → 9 (Hidden Single)
2. Riga 7 / Colonna 1 → 2 (Hidden Single)
3. Riga 8 / Colonna 5 → 6 (Hidden Single)
4. Riga 9 / Colonna 8 → 2 (Hidden Single)
5. Riga 7 / Colonna 6 → 9 (Hidden Single)
6. Riga 5 / Colonna 9 → 2 (Hidden Single)
7. Riga 6 / Colonna 9 → 6 (Hidden Single)
8. Riga 5 / Colonna 1 → 6 (Hidden Single)
9. Riga 4 / Colonna 9 → 3 (Hidden Single)
10. Riga 8 / Colonna 9 → 9 (Hidden Single)
11. Locked Candidates Type 1 (Pointing): 3 in b4 => r8c3<>3
12. Riga 8 / Colonna 2 → 3 (Hidden Single)
13. Locked Candidates Type 1 (Pointing): 8 in b4 => r12c1<>8
14. Locked Candidates Type 1 (Pointing): 1 in b7 => r8c78<>1
15. Riga 6 / Colonna 7 → 1 (Hidden Single)
16. Riga 7 / Colonna 8 → 1 (Hidden Single)
17. Locked Candidates Type 1 (Pointing): 7 in b9 => r8c13<>7
18. Locked Candidates Type 1 (Pointing): 7 in b7 => r3c2<>7
19. Locked Candidates Type 1 (Pointing): 7 in b1 => r2c5<>7
20. Hidden Pair: 2,8 in r2c57 => r2c5<>4, r2c57<>5
21. W-Wing: 4/7 in r4c3,r8c8 connected by 7 in r5c38 => r8c3<>4
22. 2-String Kite: 4 in r2c9,r8c1 (connected by r7c9,r8c8) => r2c1<>4
23. Uniqueness Test 4: 2/8 in r1c57,r2c57 => r1c57<>8
24. Discontinuous Nice Loop: 4 r2c3 -4- r2c9 -5- r7c9 =5= r8c7 =7= r4c7 -7- r4c3 -4- r2c3 => r2c3<>4
25. Locked Candidates Type 2 (Claiming): 4 in c3 => r46c1<>4
26. Simple Colors Trap: 4 (r1c1,r2c9,r8c8) / (r2c6,r7c9,r8c1) => r1c456<>4
27. Discontinuous Nice Loop: 5 r1c1 -5- r6c1 -8- r4c1 -7- r4c7 =7= r8c7 -7- r8c8 -4- r8c1 =4= r1c1 => r1c1<>5
28. Empty Rectangle: 5 in b1 (r27c9) => r7c2<>5
29. Discontinuous Nice Loop: 8 r4c5 -8- r4c1 =8= r6c1 -8- r6c8 -9- r6c5 =9= r4c5 => r4c5<>8
30. Grouped AIC: 4 4- r2c9 =4= r2c6 =1= r1c46 -1- r1c1 -4- r8c1 =4= r8c8 -4 => r13c8,r7c9<>4
31. Riga 7 / Colonna 9 → 5 (Naked Single)
32. Riga 2 / Colonna 9 → 4 (Full House)
33. Riga 8 / Colonna 7 → 7 (Naked Single)
34. Riga 8 / Colonna 8 → 4 (Full House)
35. Riga 5 / Colonna 8 → 7 (Hidden Single)
36. Riga 1 / Colonna 1 → 4 (Hidden Single)
37. Riga 5 / Colonna 4 → 8 (Hidden Single)
38. Locked Pair: 5,8 in r13c2 => r2c13,r9c2<>5
39. Riga 2 / Colonna 6 → 5 (Hidden Single)
40. Riga 5 / Colonna 6 → 3 (Naked Single)
41. Riga 5 / Colonna 3 → 5 (Full House)
42. Riga 6 / Colonna 1 → 8 (Naked Single)
43. Riga 8 / Colonna 3 → 1 (Naked Single)
44. Riga 8 / Colonna 1 → 5 (Full House)
45. Riga 4 / Colonna 1 → 7 (Naked Single)
46. Riga 2 / Colonna 1 → 1 (Full House)
47. Riga 6 / Colonna 8 → 9 (Naked Single)
48. Riga 4 / Colonna 7 → 8 (Full House)
49. Riga 2 / Colonna 3 → 7 (Naked Single)
50. Riga 4 / Colonna 3 → 4 (Naked Single)
51. Riga 4 / Colonna 5 → 9 (Full House)
52. Riga 6 / Colonna 3 → 3 (Full House)
53. Riga 2 / Colonna 7 → 2 (Naked Single)
54. Riga 2 / Colonna 5 → 8 (Full House)
55. Riga 1 / Colonna 7 → 5 (Naked Single)
56. Riga 3 / Colonna 7 → 9 (Full House)
57. Riga 1 / Colonna 2 → 8 (Naked Single)
58. Riga 3 / Colonna 2 → 5 (Full House)
59. Riga 1 / Colonna 8 → 6 (Naked Single)
60. Riga 3 / Colonna 8 → 8 (Full House)
61. Riga 1 / Colonna 6 → 1 (Naked Single)
62. Riga 1 / Colonna 4 → 3 (Naked Single)
63. Riga 1 / Colonna 5 → 2 (Full House)
64. Riga 9 / Colonna 6 → 4 (Naked Single)
65. Riga 3 / Colonna 6 → 6 (Full House)
66. Riga 7 / Colonna 4 → 7 (Naked Single)
67. Riga 9 / Colonna 2 → 7 (Naked Single)
68. Riga 7 / Colonna 2 → 4 (Full House)
69. Riga 7 / Colonna 5 → 3 (Full House)
70. Riga 3 / Colonna 4 → 4 (Naked Single)
71. Riga 3 / Colonna 5 → 7 (Full House)
72. Riga 9 / Colonna 5 → 5 (Naked Single)
73. Riga 6 / Colonna 5 → 4 (Full House)
74. Riga 6 / Colonna 4 → 5 (Full House)
75. Riga 9 / Colonna 4 → 1 (Full House)