Solution for Evil Sudoku #4158326974141

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

This Sudoku Puzzle has 74 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 5 / Column 3 → 3 (Naked Single)
  2. Row 5 / Column 7 → 7 (Naked Single)
  3. Row 5 / Column 8 → 2 (Naked Single)
  4. Row 5 / Column 2 → 4 (Full House)
  5. Row 1 / Column 9 → 4 (Hidden Single)
  6. Row 4 / Column 4 → 4 (Hidden Single)
  7. Row 7 / Column 1 → 4 (Hidden Single)
  8. Row 1 / Column 8 → 5 (Hidden Single)
  9. Locked Candidates Type 1 (Pointing): 8 in b3 => r2c16<>8
  10. Locked Candidates Type 1 (Pointing): 5 in b6 => r4c6<>5
  11. Locked Candidates Type 1 (Pointing): 3 in b7 => r8c79<>3
  12. Locked Candidates Type 2 (Claiming): 1 in r1 => r2c13,r3c12<>1
  13. Naked Triple: 1,6,7 in r247c6 => r38c6<>1, r68c6<>7, r8c6<>6
  14. Hidden Pair: 2,8 in r8c6,r9c5 => r9c5<>6, r9c5<>9
  15. 2-String Kite: 1 in r3c9,r7c6 (connected by r2c6,r3c4) => r7c9<>1
  16. Locked Candidates Type 2 (Claiming): 1 in r7 => r8c4<>1
  17. XY-Wing: 7/9/1 in r14c2,r6c3 => r1c3<>1
  18. Row 1 / Column 3 → 6 (Naked Single)
  19. XY-Chain: 1 1- r1c2 -7- r1c5 -8- r9c5 -2- r8c6 -8- r8c7 -1 => r8c2<>1
  20. AIC: 1 1- r3c9 =1= r3c4 =5= r3c6 =8= r8c6 -8- r8c7 -1 => r2c7,r89c9<>1
  21. Locked Pair: 3,8 in r2c78 => r2c19,r3c9<>3
  22. Continuous Nice Loop: 1/6/7/9 1= r1c1 =8= r3c1 =3= r8c1 =6= r8c4 -6- r2c4 =6= r2c6 -6- r4c6 -7- r4c2 =7= r1c2 =1= r1c1 =8 => r8c1<>1, r7c46<>6, r1c1,r4c5<>7, r38c1<>9
  23. Skyscraper: 7 in r1c5,r4c6 (connected by r14c2) => r2c6,r6c5<>7
  24. X-Wing: 7 r26 c14 => r78c4<>7
  25. Row 8 / Column 9 → 7 (Hidden Single)
  26. Sue de Coq: r23c4 - {15679} (r78c4 - {169}, r1c5,r3c6 - {578}) => r3c5<>8
  27. Row 3 / Column 5 → 9 (Naked Single)
  28. XY-Chain: 1 1- r2c6 -6- r4c6 -7- r6c4 -5- r3c4 -1 => r2c4<>1
  29. XY-Chain: 3 3- r4c5 -6- r4c6 -7- r7c6 -1- r7c4 -9- r7c9 -3 => r4c9<>3
  30. Row 7 / Column 9 → 3 (Hidden Single)
  31. Finned X-Wing: 9 c29 r49 fr8c2 => r9c1<>9
  32. Hidden Pair: 7,9 in r26c1 => r6c1<>1
  33. Row 6 / Column 3 → 1 (Hidden Single)
  34. Row 8 / Column 7 → 1 (Hidden Single)
  35. Row 8 / Column 6 → 8 (Hidden Single)
  36. Row 3 / Column 6 → 5 (Naked Single)
  37. Row 9 / Column 5 → 2 (Naked Single)
  38. Row 3 / Column 4 → 1 (Naked Single)
  39. Row 6 / Column 6 → 2 (Naked Single)
  40. Row 6 / Column 5 → 3 (Naked Single)
  41. Row 2 / Column 6 → 6 (Naked Single)
  42. Row 3 / Column 9 → 2 (Naked Single)
  43. Row 7 / Column 4 → 9 (Naked Single)
  44. Row 4 / Column 5 → 6 (Naked Single)
  45. Row 6 / Column 8 → 9 (Naked Single)
  46. Row 2 / Column 4 → 7 (Naked Single)
  47. Row 1 / Column 5 → 8 (Full House)
  48. Row 7 / Column 5 → 7 (Full House)
  49. Row 4 / Column 6 → 7 (Naked Single)
  50. Row 6 / Column 4 → 5 (Full House)
  51. Row 8 / Column 4 → 6 (Full House)
  52. Row 6 / Column 1 → 7 (Full House)
  53. Row 7 / Column 6 → 1 (Full House)
  54. Row 7 / Column 8 → 6 (Full House)
  55. Row 4 / Column 2 → 9 (Full House)
  56. Row 2 / Column 9 → 1 (Naked Single)
  57. Row 3 / Column 2 → 3 (Naked Single)
  58. Row 3 / Column 1 → 8 (Full House)
  59. Row 4 / Column 9 → 5 (Naked Single)
  60. Row 4 / Column 7 → 3 (Full House)
  61. Row 9 / Column 9 → 9 (Full House)
  62. Row 2 / Column 1 → 9 (Naked Single)
  63. Row 1 / Column 1 → 1 (Naked Single)
  64. Row 1 / Column 2 → 7 (Full House)
  65. Row 2 / Column 3 → 2 (Full House)
  66. Row 8 / Column 3 → 9 (Full House)
  67. Row 8 / Column 1 → 3 (Naked Single)
  68. Row 8 / Column 2 → 2 (Full House)
  69. Row 9 / Column 2 → 1 (Full House)
  70. Row 9 / Column 1 → 6 (Full House)
  71. Row 9 / Column 8 → 8 (Naked Single)
  72. Row 2 / Column 8 → 3 (Full House)
  73. Row 2 / Column 7 → 8 (Full House)
  74. Row 9 / Column 7 → 5 (Full House)
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