Solution for Evil Sudoku #4478912654341

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

This Sudoku Puzzle has 73 steps and it is solved using Naked Single, Full House, Hidden Single, Locked Candidates Type 1 (Pointing), Locked Candidates Type 2 (Claiming), Naked Triple, Hidden Pair, undefined, AIC, Locked Pair, Continuous Nice Loop, Skyscraper, Sue de Coq techniques.

Try To Solve This Puzzle

Solution Steps:

  1. Row 7 / Column 5 → 9 (Naked Single)
  2. Row 2 / Column 5 → 1 (Naked Single)
  3. Row 3 / Column 5 → 5 (Naked Single)
  4. Row 8 / Column 5 → 4 (Full House)
  5. Row 6 / Column 4 → 4 (Hidden Single)
  6. Row 1 / Column 1 → 4 (Hidden Single)
  7. Row 9 / Column 7 → 4 (Hidden Single)
  8. Row 2 / Column 1 → 7 (Hidden Single)
  9. Locked Candidates Type 1 (Pointing): 8 in b1 => r49c2<>8
  10. Locked Candidates Type 1 (Pointing): 7 in b2 => r4c4<>7
  11. Locked Candidates Type 1 (Pointing): 9 in b9 => r13c8<>9
  12. Locked Candidates Type 2 (Claiming): 3 in c1 => r79c2,r89c3<>3
  13. Naked Triple: 2,3,5 in r4c247 => r4c38<>3, r4c68<>5, r4c8<>2
  14. Hidden Pair: 1,8 in r4c8,r5c9 => r5c9<>2, r5c9<>6
  15. 2-String Kite: 3 in r1c3,r4c7 (connected by r4c2,r6c3) => r1c7<>3
  16. Locked Candidates Type 2 (Claiming): 3 in c7 => r6c8<>3
  17. XY-Wing: 5/6/3 in r7c6,r8c14 => r7c1<>3
  18. Row 7 / Column 1 → 2 (Naked Single)
  19. XY-Chain: 3 3- r3c8 -8- r4c8 -1- r5c9 -8- r5c1 -5- r8c1 -3 => r8c8<>3
  20. AIC: 3 3- r1c3 =3= r6c3 =7= r4c3 =8= r4c8 -8- r3c8 -3 => r1c89,r3c2<>3
  21. Locked Pair: 8,9 in r23c2 => r1c23,r9c2<>9
  22. Continuous Nice Loop: 2/3/5/6 8= r9c1 =3= r8c1 =5= r8c4 -5- r4c4 -2- r4c2 =2= r6c2 -2- r6c8 =2= r9c8 =9= r9c3 =8= r9c1 =3 => r46c7<>2, r9c8<>3, r5c4,r9c1<>5, r9c38<>6
  23. Skyscraper: 5 in r4c4,r5c1 (connected by r8c14) => r4c2,r5c6<>5
  24. X-Wing: 5 c26 r69 => r6c78<>5
  25. Row 1 / Column 8 → 5 (Hidden Single)
  26. Sue de Coq: r6c23 - {23567} (r6c78 - {236}, r4c3,r5c1 - {578}) => r5c3<>8
  27. Row 5 / Column 3 → 6 (Naked Single)
  28. XY-Chain: 9 9- r1c7 -6- r6c7 -3- r4c7 -5- r4c4 -2- r5c4 -9 => r1c4<>9
  29. Row 1 / Column 7 → 9 (Hidden Single)
  30. Finned X-Wing: 6 r18 c49 fr8c8 => r9c9<>6
  31. Hidden Pair: 5,6 in r9c26 => r9c6<>3
  32. Row 7 / Column 6 → 3 (Hidden Single)
  33. Row 3 / Column 8 → 3 (Hidden Single)
  34. Row 4 / Column 8 → 8 (Hidden Single)
  35. Row 4 / Column 3 → 7 (Naked Single)
  36. Row 5 / Column 9 → 1 (Naked Single)
  37. Row 4 / Column 6 → 1 (Naked Single)
  38. Row 6 / Column 3 → 3 (Naked Single)
  39. Row 5 / Column 6 → 9 (Naked Single)
  40. Row 1 / Column 3 → 1 (Naked Single)
  41. Row 4 / Column 2 → 2 (Naked Single)
  42. Row 6 / Column 7 → 6 (Naked Single)
  43. Row 2 / Column 6 → 6 (Naked Single)
  44. Row 5 / Column 4 → 2 (Naked Single)
  45. Row 1 / Column 2 → 3 (Naked Single)
  46. Row 8 / Column 3 → 9 (Naked Single)
  47. Row 9 / Column 3 → 8 (Full House)
  48. Row 4 / Column 4 → 5 (Naked Single)
  49. Row 4 / Column 7 → 3 (Full House)
  50. Row 6 / Column 6 → 7 (Full House)
  51. Row 9 / Column 6 → 5 (Full House)
  52. Row 8 / Column 4 → 6 (Full House)
  53. Row 6 / Column 2 → 5 (Naked Single)
  54. Row 6 / Column 8 → 2 (Full House)
  55. Row 5 / Column 7 → 5 (Full House)
  56. Row 2 / Column 7 → 2 (Full House)
  57. Row 5 / Column 1 → 8 (Full House)
  58. Row 1 / Column 4 → 7 (Naked Single)
  59. Row 1 / Column 9 → 6 (Full House)
  60. Row 3 / Column 4 → 9 (Full House)
  61. Row 9 / Column 1 → 3 (Naked Single)
  62. Row 8 / Column 1 → 5 (Full House)
  63. Row 9 / Column 2 → 6 (Naked Single)
  64. Row 7 / Column 2 → 1 (Full House)
  65. Row 7 / Column 8 → 6 (Full House)
  66. Row 8 / Column 8 → 1 (Naked Single)
  67. Row 8 / Column 9 → 3 (Full House)
  68. Row 9 / Column 8 → 9 (Full House)
  69. Row 9 / Column 9 → 2 (Full House)
  70. Row 2 / Column 9 → 8 (Naked Single)
  71. Row 2 / Column 2 → 9 (Full House)
  72. Row 3 / Column 2 → 8 (Full House)
  73. Row 3 / Column 9 → 7 (Full House)
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