3
2
6
1
8
7
4
9
5
7
5
1
6
9
4
2
8
3
4
9
8
2
3
5
7
6
1
6
3
8
2
4
1
7
5
9
9
2
5
3
7
6
1
4
8
1
4
7
5
8
9
6
2
3
8
7
3
9
6
4
5
1
2
4
1
2
5
3
7
8
6
9
9
5
6
8
1
2
3
7
4
This Sudoku Puzzle has 67 steps and it is solved using Hidden Single, Locked Candidates Type 1 (Pointing), Skyscraper, Naked Single, undefined, Full House, Bivalue Universal Grave + 1 techniques.
Naked Single
Explanation
Hidden Single
Explanation
Locked Candidates
Explanation
Full House
Explanation
Solution Steps:
- Row 3 / Column 7 → 7 (Hidden Single)
- Row 5 / Column 5 → 7 (Hidden Single)
- Row 6 / Column 8 → 2 (Hidden Single)
- Row 8 / Column 1 → 9 (Hidden Single)
- Row 3 / Column 4 → 2 (Hidden Single)
- Row 6 / Column 6 → 8 (Hidden Single)
- Row 2 / Column 5 → 9 (Hidden Single)
- Row 4 / Column 4 → 9 (Hidden Single)
- Row 2 / Column 7 → 2 (Hidden Single)
- Row 7 / Column 6 → 2 (Hidden Single)
- Row 7 / Column 2 → 7 (Hidden Single)
- Row 8 / Column 6 → 7 (Hidden Single)
- Row 9 / Column 8 → 7 (Hidden Single)
- Row 7 / Column 1 → 8 (Hidden Single)
- Row 2 / Column 2 → 8 (Hidden Single)
- Row 5 / Column 8 → 8 (Hidden Single)
- Row 2 / Column 4 → 6 (Hidden Single)
- Row 1 / Column 3 → 6 (Hidden Single)
- Row 8 / Column 2 → 6 (Hidden Single)
- Locked Candidates Type 1 (Pointing): 3 in b1 => r9c1<>3
- Locked Candidates Type 1 (Pointing): 3 in b4 => r9c2<>3
- Skyscraper: 5 in r6c2,r8c3 (connected by r68c4) => r5c3,r9c2<>5
- Row 9 / Column 2 → 1 (Naked Single)
- Locked Candidates Type 1 (Pointing): 1 in b4 => r5c79<>1
- Row 5 / Column 9 → 9 (Naked Single)
- Row 5 / Column 7 → 5 (Naked Single)
- Row 7 / Column 7 → 9 (Hidden Single)
- Skyscraper: 1 in r6c9,r8c8 (connected by r68c4) => r4c8,r7c9<>1
- Row 8 / Column 8 → 1 (Hidden Single)
- W-Wing: 3/4 in r2c8,r9c7 connected by 4 in r4c78 => r1c7<>3
- W-Wing: 4/1 in r1c7,r2c6 connected by 1 in r4c67 => r1c6,r2c8<>4
- Row 2 / Column 8 → 3 (Naked Single)
- Row 4 / Column 8 → 4 (Full House)
- Row 2 / Column 6 → 4 (Hidden Single)
- Row 2 / Column 1 → 1 (Full House)
- Row 5 / Column 1 → 2 (Naked Single)
- Row 5 / Column 3 → 1 (Full House)
- Row 1 / Column 1 → 3 (Hidden Single)
- Row 9 / Column 3 → 2 (Hidden Single)
- Row 7 / Column 3 → 3 (Hidden Single)
- Locked Candidates Type 1 (Pointing): 4 in b1 => r3c9<>4
- Locked Candidates Type 1 (Pointing): 5 in b1 => r3c5<>5
- X-Wing: 1 c67 r14 => r1c59<>1
- Bivalue Universal Grave + 1 => r9c9<>3, r9c9<>6
- Row 9 / Column 9 → 4 (Naked Single)
- Row 1 / Column 9 → 8 (Naked Single)
- Row 7 / Column 9 → 6 (Naked Single)
- Row 9 / Column 7 → 3 (Full House)
- Row 9 / Column 1 → 5 (Naked Single)
- Row 3 / Column 1 → 4 (Full House)
- Row 8 / Column 3 → 4 (Full House)
- Row 9 / Column 5 → 6 (Full House)
- Row 3 / Column 3 → 5 (Full House)
- Row 8 / Column 4 → 5 (Full House)
- Row 1 / Column 5 → 5 (Naked Single)
- Row 3 / Column 9 → 1 (Naked Single)
- Row 1 / Column 7 → 4 (Full House)
- Row 4 / Column 7 → 1 (Full House)
- Row 1 / Column 6 → 1 (Full House)
- Row 3 / Column 5 → 8 (Full House)
- Row 7 / Column 5 → 1 (Full House)
- Row 6 / Column 9 → 3 (Full House)
- Row 4 / Column 6 → 5 (Full House)
- Row 6 / Column 4 → 1 (Full House)
- Row 7 / Column 4 → 4 (Full House)
- Row 6 / Column 2 → 5 (Full House)
- Row 4 / Column 2 → 3 (Full House)
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