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

This Sudoku Puzzle has 40 steps and it is solved using Hidden Single, undefined, Uniqueness Test 4, Finned Swordfish, Simple Colors Trap, Naked Pair, Naked Single, Full House techniques.

Try To Solve This Puzzle

## Solution Steps:

1. Row 1 / Column 7 → 4 (Hidden Single)
2. W-Wing: 7/5 in r6c5,r9c6 connected by 5 in r69c9 => r8c5<>7
3. Row 6 / Column 5 → 7 (Hidden Single)
4. Uniqueness Test 4: 5/9 in r4c45,r8c45 => r48c4<>5
5. Finned Swordfish: 5 r169 c489 fr9c6 => r7c4<>5
6. Simple Colors Trap: 5 (r1c4,r4c5,r6c9,r9c6) / (r1c8,r4c7,r6c4,r8c5,r9c9) => r9c8<>5
7. XY-Chain: 2 2- r1c1 -7- r1c4 -5- r6c4 -2- r6c9 -5- r9c9 -2 => r9c1<>2
8. Row 1 / Column 1 → 2 (Hidden Single)
9. Row 7 / Column 3 → 2 (Hidden Single)
10. Naked Pair: 5,7 in r1c8,r3c7 => r2c78<>5, r2c78<>7
11. 2-String Kite: 7 in r1c4,r7c7 (connected by r1c8,r3c7) => r7c4<>7
12. Row 7 / Column 4 → 1 (Naked Single)
13. Row 2 / Column 7 → 1 (Hidden Single)
14. Row 2 / Column 8 → 2 (Naked Single)
15. Row 4 / Column 7 → 2 (Hidden Single)
16. Row 6 / Column 9 → 5 (Full House)
17. Row 6 / Column 4 → 2 (Full House)
18. Row 9 / Column 9 → 2 (Full House)
19. Row 4 / Column 4 → 9 (Naked Single)
20. Row 4 / Column 5 → 5 (Full House)
21. Row 8 / Column 5 → 9 (Full House)
22. Row 8 / Column 4 → 7 (Naked Single)
23. Row 1 / Column 4 → 5 (Full House)
24. Row 9 / Column 6 → 5 (Full House)
25. Row 1 / Column 8 → 7 (Full House)
26. Row 3 / Column 7 → 5 (Full House)
27. Row 7 / Column 7 → 7 (Full House)
28. Row 7 / Column 2 → 5 (Full House)
29. Row 9 / Column 8 → 1 (Naked Single)
30. Row 8 / Column 8 → 5 (Full House)
31. Row 9 / Column 1 → 7 (Full House)
32. Row 8 / Column 2 → 4 (Naked Single)
33. Row 2 / Column 2 → 7 (Full House)
34. Row 3 / Column 1 → 8 (Naked Single)
35. Row 8 / Column 1 → 1 (Full House)
36. Row 8 / Column 3 → 8 (Full House)
37. Row 2 / Column 6 → 4 (Naked Single)
38. Row 2 / Column 3 → 5 (Full House)
39. Row 3 / Column 3 → 4 (Full House)
40. Row 3 / Column 6 → 7 (Full House)