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

This Sudoku Puzzle has 79 steps and it is solved using Locked Candidates Type 1 (Pointing), undefined, Discontinuous Nice Loop, Grouped Discontinuous Nice Loop, Hidden Pair, Empty Rectangle, Hidden Single, Naked Single, Full House, AIC, Naked Triple, Hidden Rectangle techniques.

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

Solution Steps:

  1. Locked Candidates Type 1 (Pointing): 2 in b2 => r9c4<>2
  2. Locked Candidates Type 1 (Pointing): 2 in b4 => r7c3<>2
  3. Locked Candidates Type 1 (Pointing): 5 in b5 => r9c4<>5
  4. Locked Candidates Type 1 (Pointing): 6 in b7 => r3c1<>6
  5. 2-String Kite: 4 in r4c7,r7c3 (connected by r4c2,r5c3) => r7c7<>4
  6. Discontinuous Nice Loop: 1 r2c4 -1- r6c4 -5- r6c8 -2- r2c8 =2= r2c4 => r2c4<>1
  7. Discontinuous Nice Loop: 7 r2c5 -7- r2c3 -9- r6c3 =9= r6c6 =1= r6c4 -1- r3c4 =1= r2c5 => r2c5<>7
  8. Discontinuous Nice Loop: 5 r9c8 -5- r9c5 =5= r8c5 =1= r2c5 -1- r3c4 =1= r6c4 =5= r6c8 -5- r9c8 => r9c8<>5
  9. Grouped Discontinuous Nice Loop: 5 r3c1 -5- r789c1 =5= r7c3 =4= r5c3 -4- r4c2 -8- r5c1 =8= r3c1 => r3c1<>5
  10. Locked Candidates Type 1 (Pointing): 5 in b1 => r7c3<>5
  11. Hidden Pair: 5,6 in r13c3 => r13c3<>7, r1c3<>9
  12. Empty Rectangle: 7 in b9 (r27c3) => r2c8<>7
  13. XY-Chain: 1 1- r3c1 -8- r5c1 -9- r6c3 -2- r6c8 -5- r6c4 -1 => r3c4<>1
  14. Row 6 / Column 4 → 1 (Hidden Single)
  15. Row 6 / Column 6 → 9 (Naked Single)
  16. Row 6 / Column 3 → 2 (Naked Single)
  17. Row 6 / Column 8 → 5 (Full House)
  18. Row 2 / Column 5 → 1 (Hidden Single)
  19. Row 4 / Column 4 → 5 (Hidden Single)
  20. Row 5 / Column 7 → 2 (Hidden Single)
  21. Empty Rectangle: 3 in b8 (r4c67) => r8c7<>3
  22. AIC: 4 4- r1c8 =4= r1c9 =9= r1c2 -9- r2c3 =9= r5c3 =4= r5c9 -4- r4c7 =4= r9c7 -4 => r79c8<>4
  23. Row 1 / Column 8 → 4 (Hidden Single)
  24. X-Wing: 4 r49 c27 => r7c2<>4
  25. Discontinuous Nice Loop: 7 r3c2 -7- r2c3 -9- r5c3 =9= r5c1 =8= r3c1 =1= r3c2 => r3c2<>7
  26. Discontinuous Nice Loop: 5 r7c9 -5- r7c1 -1- r3c1 -8- r5c1 -9- r5c3 -4- r5c9 =4= r7c9 => r7c9<>5
  27. Locked Candidates Type 1 (Pointing): 5 in b9 => r3c7<>5
  28. Naked Triple: 1,3,8 in r3c127 => r3c489<>3, r3c48<>8
  29. XY-Wing: 3/4/8 in r34c7,r4c2 => r3c2<>8
  30. Hidden Rectangle: 2/7 in r2c48,r3c48 => r2c4<>7
  31. Discontinuous Nice Loop: 3 r7c7 -3- r3c7 -8- r3c1 =8= r5c1 -8- r4c2 -4- r4c7 -3- r7c7 => r7c7<>3
  32. XY-Wing: 1/5/8 in r37c1,r7c7 => r3c7<>8
  33. Row 3 / Column 7 → 3 (Naked Single)
  34. Row 3 / Column 2 → 1 (Naked Single)
  35. Row 4 / Column 7 → 4 (Naked Single)
  36. Row 5 / Column 9 → 3 (Full House)
  37. Row 3 / Column 1 → 8 (Naked Single)
  38. Row 4 / Column 2 → 8 (Naked Single)
  39. Row 4 / Column 6 → 3 (Full House)
  40. Row 5 / Column 1 → 9 (Naked Single)
  41. Row 5 / Column 3 → 4 (Full House)
  42. Row 7 / Column 3 → 7 (Naked Single)
  43. Row 2 / Column 3 → 9 (Naked Single)
  44. Row 7 / Column 2 → 2 (Naked Single)
  45. Row 7 / Column 9 → 4 (Naked Single)
  46. Row 8 / Column 2 → 9 (Naked Single)
  47. Row 2 / Column 9 → 7 (Naked Single)
  48. Row 8 / Column 7 → 5 (Naked Single)
  49. Row 9 / Column 2 → 4 (Naked Single)
  50. Row 2 / Column 2 → 3 (Naked Single)
  51. Row 1 / Column 2 → 7 (Full House)
  52. Row 3 / Column 8 → 2 (Naked Single)
  53. Row 3 / Column 9 → 5 (Naked Single)
  54. Row 1 / Column 9 → 9 (Full House)
  55. Row 2 / Column 8 → 8 (Full House)
  56. Row 2 / Column 4 → 2 (Full House)
  57. Row 7 / Column 7 → 8 (Naked Single)
  58. Row 9 / Column 7 → 9 (Full House)
  59. Row 3 / Column 3 → 6 (Naked Single)
  60. Row 1 / Column 3 → 5 (Full House)
  61. Row 3 / Column 4 → 7 (Full House)
  62. Row 7 / Column 8 → 3 (Naked Single)
  63. Row 7 / Column 6 → 1 (Naked Single)
  64. Row 7 / Column 1 → 5 (Full House)
  65. Row 9 / Column 4 → 8 (Naked Single)
  66. Row 8 / Column 6 → 7 (Naked Single)
  67. Row 9 / Column 1 → 6 (Naked Single)
  68. Row 8 / Column 1 → 1 (Full House)
  69. Row 5 / Column 4 → 6 (Naked Single)
  70. Row 1 / Column 4 → 3 (Full House)
  71. Row 8 / Column 5 → 3 (Naked Single)
  72. Row 8 / Column 8 → 6 (Full House)
  73. Row 9 / Column 8 → 7 (Full House)
  74. Row 9 / Column 5 → 5 (Naked Single)
  75. Row 9 / Column 6 → 2 (Full House)
  76. Row 5 / Column 6 → 8 (Naked Single)
  77. Row 1 / Column 6 → 6 (Full House)
  78. Row 1 / Column 5 → 8 (Full House)
  79. Row 5 / Column 5 → 7 (Full House)
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