Solution for Hard Sudoku #1468431257918
7
5
2
1
8
6
4
3
9
6
4
1
3
7
9
5
8
2
8
9
3
4
5
2
1
6
7
2
1
7
8
4
5
6
9
3
9
6
8
7
2
3
4
1
5
3
4
5
6
1
9
7
2
8
5
2
1
3
6
4
9
7
8
8
3
4
2
9
7
1
5
6
9
7
6
5
8
1
2
3
4
This Sudoku Puzzle has 61 steps and it is solved using Hidden Single, Locked Triple, Naked Single, Locked Candidates Type 1 (Pointing), Naked Pair, undefined, Skyscraper, Full House techniques.
Naked Single
Explanation
Hidden Single
Explanation
Locked Candidates
Explanation
Full House
Explanation
Solution Steps:
- Row 2 / Column 2 → 8 (Hidden Single)
- Locked Triple: 3,4,8 in r7c456 => r7c37,r8c46,r9c5<>4, r7c7,r9c5<>3, r8c46<>8
- Row 9 / Column 5 → 5 (Naked Single)
- Row 3 / Column 5 → 8 (Naked Single)
- Locked Candidates Type 1 (Pointing): 2 in b2 => r3c3<>2
- Locked Candidates Type 1 (Pointing): 2 in b8 => r8c78<>2
- Locked Candidates Type 1 (Pointing): 7 in b8 => r8c2<>7
- Naked Pair: 3,4 in r17c5 => r46c5<>3, r6c5<>4
- X-Wing: 1 r37 c37 => r2c37,r458c7,r568c3<>1
- Skyscraper: 1 in r2c1,r5c2 (connected by r25c8) => r46c1<>1
- Row 2 / Column 1 → 1 (Hidden Single)
- Row 3 / Column 7 → 1 (Hidden Single)
- Row 7 / Column 7 → 9 (Naked Single)
- Row 7 / Column 3 → 1 (Naked Single)
- Row 2 / Column 3 → 6 (Hidden Single)
- Row 8 / Column 3 → 4 (Naked Single)
- Row 8 / Column 2 → 6 (Naked Single)
- Row 8 / Column 7 → 5 (Naked Single)
- Row 9 / Column 2 → 7 (Naked Single)
- Row 9 / Column 1 → 9 (Full House)
- Row 1 / Column 2 → 5 (Naked Single)
- Row 3 / Column 3 → 9 (Naked Single)
- Row 4 / Column 2 → 1 (Naked Single)
- Row 5 / Column 2 → 4 (Full House)
- Row 1 / Column 3 → 2 (Naked Single)
- Row 1 / Column 1 → 7 (Full House)
- Row 3 / Column 6 → 2 (Naked Single)
- Row 3 / Column 4 → 5 (Full House)
- Row 4 / Column 5 → 6 (Naked Single)
- Row 6 / Column 3 → 3 (Naked Single)
- Row 5 / Column 3 → 5 (Full House)
- Row 8 / Column 6 → 7 (Naked Single)
- Row 4 / Column 1 → 2 (Naked Single)
- Row 6 / Column 1 → 6 (Full House)
- Row 6 / Column 5 → 1 (Naked Single)
- Row 5 / Column 6 → 3 (Naked Single)
- Row 8 / Column 4 → 2 (Naked Single)
- Row 4 / Column 7 → 3 (Naked Single)
- Row 6 / Column 9 → 8 (Naked Single)
- Row 4 / Column 6 → 8 (Naked Single)
- Row 4 / Column 9 → 5 (Full House)
- Row 5 / Column 4 → 7 (Naked Single)
- Row 6 / Column 4 → 4 (Full House)
- Row 6 / Column 8 → 2 (Full House)
- Row 5 / Column 7 → 6 (Naked Single)
- Row 5 / Column 8 → 1 (Full House)
- Row 2 / Column 7 → 4 (Naked Single)
- Row 9 / Column 7 → 2 (Full House)
- Row 8 / Column 9 → 1 (Naked Single)
- Row 8 / Column 8 → 8 (Full House)
- Row 7 / Column 6 → 4 (Naked Single)
- Row 2 / Column 6 → 9 (Full House)
- Row 2 / Column 4 → 3 (Naked Single)
- Row 1 / Column 5 → 4 (Full House)
- Row 7 / Column 5 → 3 (Full House)
- Row 2 / Column 8 → 5 (Full House)
- Row 7 / Column 4 → 8 (Full House)
- Row 9 / Column 8 → 3 (Naked Single)
- Row 1 / Column 8 → 9 (Full House)
- Row 1 / Column 9 → 3 (Full House)
- Row 9 / Column 9 → 4 (Full House)
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