Solution for Evil Sudoku #1221713524895

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

This Sudoku Puzzle has 47 steps and it is solved using Hidden Single, Locked Pair, Naked Single, Full House, Give Up techniques.

Naked Single Explanation
Hidden Single Explanation
Full House Explanation
Try To Solve This Puzzle

Solution Steps:

  1. Row 7 / Column 1 → 4 (Hidden Single)
  2. Locked Pair: 6,9 in r46c4 => r2379c4,r46c6,r5c5<>6, r2379c4,r46c6,r5c5<>9
  3. Row 7 / Column 4 → 2 (Naked Single)
  4. Row 5 / Column 5 → 3 (Naked Single)
  5. Row 6 / Column 6 → 4 (Naked Single)
  6. Row 4 / Column 6 → 4 (Naked Single)
  7. Row 8 / Column 8 → 2 (Hidden Single)
  8. Row 9 / Column 2 → 2 (Hidden Single)
  9. Row 5 / Column 7 → 4 (Hidden Single)
  10. Row 3 / Column 3 → 2 (Hidden Single)
  11. Row 8 / Column 6 → 7 (Hidden Single)
  12. Row 9 / Column 4 → 8 (Naked Single)
  13. Row 3 / Column 4 → 1 (Naked Single)
  14. Row 2 / Column 4 → 7 (Naked Single)
  15. Row 5 / Column 8 → 7 (Hidden Single)
  16. Row 9 / Column 9 → 7 (Hidden Single)
  17. Row 8 / Column 7 → 8 (Hidden Single)
  18. Row 9 / Column 1 → 5 (Hidden Single)
  19. Row 3 / Column 2 → 4 (Hidden Single)
  20. Row 1 / Column 3 → 7 (Hidden Single)
  21. Row 7 / Column 6 → 3 (Hidden Single)
  22. Row 9 / Column 7 → 3 (Hidden Single)
  23. Row 8 / Column 1 → 3 (Hidden Single)
  24. Row 1 / Column 9 → 4 (Hidden Single)
  25. Row 7 / Column 5 → 5 (Hidden Single)
  26. Row 9 / Column 5 → 6 (Hidden Single)
  27. Row 3 / Column 9 → 8 (Hidden Single)
  28. Row 3 / Column 5 → 9 (Naked Single)
  29. Row 1 / Column 5 → 8 (Full House)
  30. Row 3 / Column 1 → 6 (Naked Single)
  31. Row 1 / Column 1 → 9 (Full House)
  32. Row 3 / Column 6 → 5 (Full House)
  33. Row 5 / Column 1 → 9 (Full House)
  34. Row 1 / Column 6 → 6 (Full House)
  35. Row 1 / Column 8 → 5 (Full House)
  36. Row 5 / Column 2 → 6 (Naked Single)
  37. Row 5 / Column 3 → 6 (Naked Single)
  38. Row 8 / Column 2 → 9 (Full House)
  39. Row 8 / Column 3 → 9 (Full House)
  40. Row 5 / Column 9 → 6 (Naked Single)
  41. Row 6 / Column 7 → 5 (Hidden Single)
  42. Row 6 / Column 2 → 8 (Naked Single)
  43. Row 6 / Column 8 → 9 (Naked Single)
  44. Row 6 / Column 4 → 6 (Full House)
  45. Row 4 / Column 4 → 9 (Full House)
  46. Row 4 / Column 8 → 8 (Naked Single)
  47. Give Up: Don't know how to proceed!
Show More...