Passaggi della soluzione:

1. Riga 1 / Colonna 3 → 9 (Hidden Single)
2. Riga 6 / Colonna 1 → 9 (Hidden Single)
3. Riga 5 / Colonna 4 → 2 (Hidden Single)
4. Riga 7 / Colonna 2 → 4 (Hidden Single)
5. Riga 5 / Colonna 6 → 9 (Hidden Single)
6. Riga 3 / Colonna 3 → 2 (Hidden Single)
7. Riga 7 / Colonna 5 → 9 (Hidden Single)
8. Riga 3 / Colonna 6 → 4 (Hidden Single)
9. Riga 8 / Colonna 4 → 4 (Hidden Single)
10. Riga 9 / Colonna 7 → 9 (Hidden Single)
11. Locked Candidates Type 1 (Pointing): 8 in b1 => r2c5789<>8
12. Locked Candidates Type 1 (Pointing): 1 in b5 => r12c5<>1
13. Locked Candidates Type 1 (Pointing): 8 in b5 => r4c79<>8
14. Locked Candidates Type 1 (Pointing): 5 in b8 => r1c6<>5
15. Riga 1 / Colonna 6 → 8 (Naked Single)
16. Riga 4 / Colonna 6 → 6 (Naked Single)
17. Riga 4 / Colonna 9 → 3 (Naked Single)
18. Riga 6 / Colonna 5 → 1 (Naked Single)
19. Riga 4 / Colonna 5 → 8 (Full House)
20. 2-String Kite: 1 in r2c1,r5c8 (connected by r4c1,r5c2) => r2c8<>1
21. Finned X-Wing: 6 c15 r28 fr9c1 => r8c3<>6
22. Discontinuous Nice Loop: 7 r2c3 -7- r4c3 =7= r4c1 =1= r2c1 =8= r2c3 => r2c3<>7
23. Discontinuous Nice Loop: 6 r7c3 -6- r5c3 -3- r5c2 =3= r9c2 =5= r7c3 => r7c3<>6
24. Discontinuous Nice Loop: 7 r7c3 -7- r4c3 =7= r4c1 =1= r2c1 =8= r2c3 =5= r7c3 => r7c3<>7
25. Discontinuous Nice Loop: 8 r7c8 -8- r3c8 -1- r3c4 -6- r7c4 =6= r7c8 => r7c8<>8
26. Grouped Discontinuous Nice Loop: 1 r1c2 -1- r1c4 =1= r3c4 =6= r3c2 =5= r3c7 -5- r2c9 -7- r1c89 =7= r1c2 => r1c2<>1
27. W-Wing: 7/5 in r1c2,r2c9 connected by 5 in r3c27 => r1c89,r2c12<>7
28. Riga 1 / Colonna 2 → 7 (Hidden Single)
29. AIC: 5/8 8- r2c3 =8= r2c1 =1= r4c1 -1- r4c7 =1= r5c8 -1- r1c8 =1= r1c4 -1- r3c4 -6- r7c4 =6= r7c8 =7= r7c6 =5= r7c3 -5 => r2c3<>5, r7c3<>8
30. Riga 7 / Colonna 3 → 5 (Hidden Single)
31. Riga 7 / Colonna 6 → 7 (Naked Single)
32. Riga 9 / Colonna 6 → 5 (Full House)
33. Discontinuous Nice Loop: 3/6/8 r9c8 =7= r9c1 -7- r4c1 -1- r4c7 -4- r2c7 =4= r2c8 =7= r9c8 => r9c8<>3, r9c8<>6, r9c8<>8
34. Riga 9 / Colonna 8 → 7 (Naked Single)
35. Riga 2 / Colonna 9 → 7 (Hidden Single)
36. Discontinuous Nice Loop: 3/8 r8c7 =2= r8c9 -2- r1c9 -5- r6c9 =5= r6c7 =2= r8c7 => r8c7<>3, r8c7<>8
37. Riga 8 / Colonna 7 → 2 (Naked Single)
38. Locked Candidates Type 1 (Pointing): 3 in b9 => r7c4<>3
39. Naked Pair: 6,8 in r58c9 => r6c9<>6
40. W-Wing: 8/6 in r2c3,r8c9 connected by 6 in r28c5 => r8c3<>8
41. Riga 2 / Colonna 3 → 8 (Hidden Single)
42. Locked Candidates Type 2 (Claiming): 6 in c3 => r5c2<>6
43. W-Wing: 3/6 in r5c3,r8c5 connected by 6 in r58c9 => r8c3<>3
44. Riga 8 / Colonna 3 → 7 (Naked Single)
45. Riga 4 / Colonna 3 → 4 (Naked Single)
46. Riga 4 / Colonna 7 → 1 (Naked Single)
47. Riga 4 / Colonna 1 → 7 (Full House)
48. Riga 6 / Colonna 3 → 6 (Naked Single)
49. Riga 5 / Colonna 3 → 3 (Full House)
50. Riga 5 / Colonna 2 → 1 (Full House)
51. Riga 8 / Colonna 5 → 3 (Hidden Single)
52. Riga 1 / Colonna 5 → 5 (Naked Single)
53. Riga 2 / Colonna 5 → 6 (Full House)
54. Riga 1 / Colonna 9 → 2 (Naked Single)
55. Riga 2 / Colonna 1 → 1 (Naked Single)
56. Riga 2 / Colonna 2 → 5 (Naked Single)
57. Riga 3 / Colonna 2 → 6 (Full House)
58. Riga 9 / Colonna 2 → 3 (Full House)
59. Riga 3 / Colonna 4 → 1 (Naked Single)
60. Riga 1 / Colonna 4 → 3 (Full House)
61. Riga 1 / Colonna 8 → 1 (Full House)
62. Riga 6 / Colonna 9 → 5 (Naked Single)
63. Riga 3 / Colonna 8 → 8 (Naked Single)
64. Riga 3 / Colonna 7 → 5 (Full House)
65. Riga 6 / Colonna 7 → 4 (Naked Single)
66. Riga 6 / Colonna 8 → 2 (Full House)
67. Riga 5 / Colonna 8 → 6 (Naked Single)
68. Riga 5 / Colonna 9 → 8 (Full House)
69. Riga 8 / Colonna 9 → 6 (Full House)
70. Riga 8 / Colonna 1 → 8 (Full House)
71. Riga 9 / Colonna 1 → 6 (Full House)
72. Riga 9 / Colonna 4 → 8 (Full House)
73. Riga 7 / Colonna 4 → 6 (Full House)
74. Riga 2 / Colonna 7 → 3 (Naked Single)
75. Riga 2 / Colonna 8 → 4 (Full House)
76. Riga 7 / Colonna 8 → 3 (Full House)
77. Riga 7 / Colonna 7 → 8 (Full House)