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

This Sudoku Puzzle has 50 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Locked Candidates Type 2 (Claiming), Naked Single, Full House, undefined, AIC, Hidden Pair, Uniqueness Test 6, Bivalue Universal Grave + 1 techniques.

Naked Single Explanation
Hidden Single Explanation
Hidden Pair Explanation
Locked Candidates Explanation
Locked Candidates Explanation
Full House Explanation
Try To Solve This Puzzle

Solution Steps:

  1. Row 4 / Column 4 → 5 (Hidden Single)
  2. Row 4 / Column 5 → 7 (Hidden Single)
  3. Locked Candidates Type 1 (Pointing): 9 in b1 => r3c9<>9
  4. Locked Candidates Type 1 (Pointing): 2 in b8 => r7c13<>2
  5. Locked Candidates Type 1 (Pointing): 9 in b8 => r56c5<>9
  6. Locked Candidates Type 2 (Claiming): 3 in r1 => r3c12<>3
  7. Locked Candidates Type 2 (Claiming): 3 in c2 => r45c3<>3
  8. Locked Candidates Type 2 (Claiming): 4 in c6 => r6c45<>4
  9. Row 6 / Column 4 → 2 (Naked Single)
  10. Row 7 / Column 4 → 4 (Naked Single)
  11. Row 8 / Column 5 → 9 (Naked Single)
  12. Row 7 / Column 5 → 2 (Full House)
  13. Row 2 / Column 5 → 4 (Hidden Single)
  14. Finned X-Wing: 2 c29 r34 fr5c2 => r4c3<>2
  15. XY-Chain: 1 1- r3c6 -3- r3c9 -2- r4c9 -9- r6c7 -1 => r6c6<>1
  16. AIC: 3/6 3- r2c4 =3= r2c9 =9= r4c9 =2= r4c2 =3= r4c6 -3- r5c4 -6 => r5c4<>3, r2c4<>6
  17. Row 5 / Column 4 → 6 (Naked Single)
  18. Row 2 / Column 4 → 3 (Full House)
  19. Row 2 / Column 9 → 9 (Naked Single)
  20. Row 2 / Column 7 → 6 (Full House)
  21. Row 3 / Column 6 → 1 (Naked Single)
  22. Row 3 / Column 5 → 6 (Full House)
  23. Row 4 / Column 9 → 2 (Naked Single)
  24. Row 3 / Column 9 → 3 (Full House)
  25. Row 1 / Column 7 → 2 (Full House)
  26. Hidden Pair: 2,8 in r59c3 => r5c3<>9
  27. Uniqueness Test 6: 3/9 in r4c26,r5c26 => r4c6,r5c2<>3
  28. Row 4 / Column 2 → 3 (Hidden Single)
  29. Row 5 / Column 6 → 3 (Hidden Single)
  30. Bivalue Universal Grave + 1 => r6c1<>4, r6c1<>8
  31. Row 6 / Column 1 → 9 (Naked Single)
  32. Row 3 / Column 1 → 2 (Naked Single)
  33. Row 3 / Column 2 → 9 (Full House)
  34. Row 5 / Column 2 → 2 (Full House)
  35. Row 4 / Column 3 → 4 (Naked Single)
  36. Row 5 / Column 3 → 8 (Full House)
  37. Row 4 / Column 6 → 9 (Full House)
  38. Row 6 / Column 6 → 4 (Full House)
  39. Row 6 / Column 7 → 1 (Naked Single)
  40. Row 5 / Column 7 → 9 (Full House)
  41. Row 5 / Column 5 → 1 (Full House)
  42. Row 6 / Column 5 → 8 (Full House)
  43. Row 7 / Column 1 → 3 (Naked Single)
  44. Row 7 / Column 3 → 9 (Full House)
  45. Row 9 / Column 1 → 8 (Naked Single)
  46. Row 9 / Column 3 → 2 (Full House)
  47. Row 8 / Column 3 → 6 (Naked Single)
  48. Row 1 / Column 3 → 3 (Full House)
  49. Row 1 / Column 1 → 6 (Full House)
  50. Row 8 / Column 1 → 4 (Full House)
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