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

This Sudoku Puzzle has 51 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Locked Pair, Naked Single, Full House, Naked Pair, Uniqueness Test 1, Uniqueness Test 2, Hidden Rectangle, AIC, Uniqueness Test 4, undefined, Give Up techniques.

Try To Solve This Puzzle

Solution Steps:

  1. Row 5 / Column 6 → 9 (Hidden Single)
  2. Row 4 / Column 3 → 6 (Hidden Single)
  3. Row 3 / Column 4 → 6 (Hidden Single)
  4. Row 3 / Column 2 → 7 (Hidden Single)
  5. Row 9 / Column 1 → 6 (Hidden Single)
  6. Row 1 / Column 7 → 1 (Hidden Single)
  7. Row 7 / Column 9 → 4 (Hidden Single)
  8. Row 5 / Column 1 → 5 (Hidden Single)
  9. Row 5 / Column 2 → 4 (Hidden Single)
  10. Row 9 / Column 3 → 4 (Hidden Single)
  11. Row 8 / Column 3 → 5 (Hidden Single)
  12. Locked Candidates Type 1 (Pointing): 1 in b1 => r7c3<>1
  13. Locked Candidates Type 1 (Pointing): 3 in b1 => r7c1<>3
  14. Locked Candidates Type 1 (Pointing): 9 in b1 => r7c3<>9
  15. Locked Pair: 2,8 in r7c13 => r7c247,r89c2<>2, r7c245,r89c2<>8
  16. Row 9 / Column 2 → 9 (Naked Single)
  17. Locked Candidates Type 1 (Pointing): 3 in b3 => r6c9<>3
  18. Locked Candidates Type 1 (Pointing): 5 in b3 => r6c9<>5
  19. Locked Candidates Type 1 (Pointing): 9 in b3 => r8c8<>9
  20. Locked Candidates Type 1 (Pointing): 7 in b9 => r5c7<>7
  21. Row 5 / Column 7 → 2 (Naked Single)
  22. Row 5 / Column 4 → 8 (Naked Single)
  23. Row 5 / Column 9 → 7 (Full House)
  24. Row 9 / Column 7 → 7 (Naked Single)
  25. Row 7 / Column 7 → 9 (Naked Single)
  26. Row 8 / Column 7 → 6 (Naked Single)
  27. Row 8 / Column 5 → 9 (Hidden Single)
  28. Locked Candidates Type 1 (Pointing): 2 in b9 => r8c6<>2
  29. Locked Candidates Type 1 (Pointing): 8 in b9 => r8c6<>8
  30. Naked Pair: 2,8 in r17c3 => r2c3<>8, r3c3<>2
  31. Uniqueness Test 1: 2/8 in r1c13,r7c13 => r1c1<>2, r1c1<>8
  32. Uniqueness Test 2: 3/5 in r4c57,r6c57 => r13c5,r6c6<>4
  33. Hidden Rectangle: 3/4 in r1c16,r3c16 => r3c6<>3
  34. AIC: 2 2- r1c3 -8- r2c1 =8= r2c6 =1= r2c3 =9= r2c8 -9- r3c8 -2 => r1c89,r3c1<>2
  35. Row 1 / Column 3 → 2 (Hidden Single)
  36. Row 7 / Column 3 → 8 (Naked Single)
  37. Row 7 / Column 1 → 2 (Naked Single)
  38. Row 2 / Column 1 → 8 (Hidden Single)
  39. Uniqueness Test 4: 3/4 in r1c16,r3c16 => r1c6<>3
  40. AIC: 4 4- r1c1 -3- r1c9 -6- r6c9 -8- r6c2 -2- r6c6 =2= r9c6 =8= r1c6 =4= r3c6 -4 => r1c6,r3c1<>4
  41. Row 1 / Column 6 → 8 (Naked Single)
  42. Row 3 / Column 1 → 3 (Naked Single)
  43. Row 1 / Column 1 → 4 (Full House)
  44. Row 3 / Column 6 → 4 (Hidden Single)
  45. Row 9 / Column 5 → 8 (Hidden Single)
  46. XYZ-Wing: 3/5/7 in r1c5,r2c49 => r2c6<>3
  47. Naked Pair: 1,5 in r2c6,r3c5 => r2c4<>5
  48. Naked Pair: 3,7 in r27c4 => r4c4<>3
  49. XYZ-Wing: 2/3/5 in r4c4,r6c67 => r6c5<>5
  50. XY-Chain: 3 3- r1c5 -7- r2c4 -3- r2c9 -5- r2c6 -1- r8c6 -3 => r7c5<>3
  51. Give Up: Don't know how to proceed!
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