Analysis of xx-top500-305-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 36.....4.2..5........1..7...41.........2....8......3......6..1.7...4............5 initial

Autosolve

position: 365.7.14.2175.4..64..1.675..416.35275..21.4686..45.391...765.14756.412..1.43..675 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # F1: 8,9 => CTR => F1: 2
* PRF # F1: 2 => SOL
* PRF # F1: 2,9 => SOL
* DIS # F1: 8 => CTR => F1: 2,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* CNT  14 HDP CHAINS /  14 HYP OPENED

See Appendix: Full HDP Chains for full list of HDP chains.

Pair Reduction

Pair Reduction

The following important HDP chains were detected:

* DIS # F1: 8,9 => CTR => F1: 2
* PRF F1: 2 => SOL
* STA F1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED

See Appendix: Full HDP Chains for full list of HDP chains.

Details

Positions

36.....4.2..5........1..7...41.........2....8......3......6..1.7...4............5 initial
365.7.14.2175.4..64..1.675..416.35275..21.4686..45.391...765.14756.412..1.43..675 autosolve
365872149217594836489136752941683527573219468628457391832765914756941283194328675 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (25)
B3: 8,9
C3: 8,9
D1: 8,9
E2: 3,9
E3: 2,3
I1: 2,9
G2: 8,9
H2: 3,8
I3: 2,3
A4: 8,9
B5: 3,7
C5: 3,9
B6: 2,7
C6: 2,8
E4: 8,9
F5: 7,9
F6: 7,8
A7: 8,9
B7: 2,3
C7: 2,3
B9: 8,9
D8: 8,9
G7: 8,9
H8: 3,8
I8: 3,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
F1,E3: 2.. / F1 = 2  =>  0 pairs (*) / E3 = 2  =>  0 pairs (X)
I1,I3: 2.. / I1 = 2  =>  0 pairs (X) / I3 = 2  =>  0 pairs (_)
B6,C6: 2.. / B6 = 2  =>  0 pairs (*) / C6 = 2  =>  0 pairs (X)
B7,C7: 2.. / B7 = 2  =>  0 pairs (X) / C7 = 2  =>  0 pairs (_)
E9,F9: 2.. / E9 = 2  =>  0 pairs (*) / F9 = 2  =>  0 pairs (X)
F1,I1: 2.. / F1 = 2  =>  0 pairs (*) / I1 = 2  =>  0 pairs (X)
E3,I3: 2.. / E3 = 2  =>  0 pairs (X) / I3 = 2  =>  0 pairs (_)
B6,B7: 2.. / B6 = 2  =>  0 pairs (*) / B7 = 2  =>  0 pairs (X)
C6,C7: 2.. / C6 = 2  =>  0 pairs (X) / C7 = 2  =>  0 pairs (_)
E3,E9: 2.. / E3 = 2  =>  0 pairs (X) / E9 = 2  =>  0 pairs (_)
F1,F9: 2.. / F1 = 2  =>  0 pairs (*) / F9 = 2  =>  0 pairs (X)
E2,E3: 3.. / E2 = 3  =>  0 pairs (X) / E3 = 3  =>  0 pairs (_)
H2,I3: 3.. / H2 = 3  =>  0 pairs (*) / I3 = 3  =>  0 pairs (X)
B5,C5: 3.. / B5 = 3  =>  0 pairs (X) / C5 = 3  =>  0 pairs (_)
B7,C7: 3.. / B7 = 3  =>  0 pairs (*) / C7 = 3  =>  0 pairs (X)
H8,I8: 3.. / H8 = 3  =>  0 pairs (X) / I8 = 3  =>  0 pairs (_)
E2,H2: 3.. / E2 = 3  =>  0 pairs (X) / H2 = 3  =>  0 pairs (_)
E3,I3: 3.. / E3 = 3  =>  0 pairs (*) / I3 = 3  =>  0 pairs (X)
B5,B7: 3.. / B5 = 3  =>  0 pairs (X) / B7 = 3  =>  0 pairs (_)
C5,C7: 3.. / C5 = 3  =>  0 pairs (*) / C7 = 3  =>  0 pairs (X)
H2,H8: 3.. / H2 = 3  =>  0 pairs (*) / H8 = 3  =>  0 pairs (X)
I3,I8: 3.. / I3 = 3  =>  0 pairs (X) / I8 = 3  =>  0 pairs (_)
B5,B6: 7.. / B5 = 7  =>  0 pairs (*) / B6 = 7  =>  0 pairs (X)
F5,F6: 7.. / F5 = 7  =>  0 pairs (X) / F6 = 7  =>  0 pairs (_)
B5,F5: 7.. / B5 = 7  =>  0 pairs (*) / F5 = 7  =>  0 pairs (X)
B6,F6: 7.. / B6 = 7  =>  0 pairs (X) / F6 = 7  =>  0 pairs (_)
B3,C3: 8.. / B3 = 8  =>  0 pairs (*) / C3 = 8  =>  0 pairs (X)
D1,F1: 8.. / D1 = 8  =>  0 pairs (*) / F1 = 8  =>  0 pairs (X)
G2,H2: 8.. / G2 = 8  =>  0 pairs (*) / H2 = 8  =>  0 pairs (X)
A4,C6: 8.. / A4 = 8  =>  0 pairs (X) / C6 = 8  =>  0 pairs (_)
E4,F6: 8.. / E4 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
A7,B9: 8.. / A7 = 8  =>  0 pairs (*) / B9 = 8  =>  0 pairs (X)
G7,H8: 8.. / G7 = 8  =>  0 pairs (X) / H8 = 8  =>  0 pairs (_)
A4,E4: 8.. / A4 = 8  =>  0 pairs (X) / E4 = 8  =>  0 pairs (_)
C6,F6: 8.. / C6 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
A7,G7: 8.. / A7 = 8  =>  0 pairs (*) / G7 = 8  =>  0 pairs (X)
D8,H8: 8.. / D8 = 8  =>  0 pairs (X) / H8 = 8  =>  0 pairs (_)
A4,A7: 8.. / A4 = 8  =>  0 pairs (X) / A7 = 8  =>  0 pairs (_)
B3,B9: 8.. / B3 = 8  =>  0 pairs (*) / B9 = 8  =>  0 pairs (X)
C3,C6: 8.. / C3 = 8  =>  0 pairs (X) / C6 = 8  =>  0 pairs (_)
D1,D8: 8.. / D1 = 8  =>  0 pairs (*) / D8 = 8  =>  0 pairs (X)
E4,E9: 8.. / E4 = 8  =>  0 pairs (*) / E9 = 8  =>  0 pairs (X)
G2,G7: 8.. / G2 = 8  =>  0 pairs (*) / G7 = 8  =>  0 pairs (X)
H2,H8: 8.. / H2 = 8  =>  0 pairs (X) / H8 = 8  =>  0 pairs (_)
B3,C3: 9.. / B3 = 9  =>  0 pairs (X) / C3 = 9  =>  0 pairs (_)
I1,G2: 9.. / I1 = 9  =>  0 pairs (*) / G2 = 9  =>  0 pairs (X)
A4,C5: 9.. / A4 = 9  =>  0 pairs (*) / C5 = 9  =>  0 pairs (X)
E4,F5: 9.. / E4 = 9  =>  0 pairs (X) / F5 = 9  =>  0 pairs (_)
A7,B9: 9.. / A7 = 9  =>  0 pairs (X) / B9 = 9  =>  0 pairs (_)
G7,I8: 9.. / G7 = 9  =>  0 pairs (*) / I8 = 9  =>  0 pairs (X)
E2,G2: 9.. / E2 = 9  =>  0 pairs (*) / G2 = 9  =>  0 pairs (X)
A4,E4: 9.. / A4 = 9  =>  0 pairs (*) / E4 = 9  =>  0 pairs (X)
C5,F5: 9.. / C5 = 9  =>  0 pairs (X) / F5 = 9  =>  0 pairs (_)
A7,G7: 9.. / A7 = 9  =>  0 pairs (X) / G7 = 9  =>  0 pairs (_)
D8,I8: 9.. / D8 = 9  =>  0 pairs (*) / I8 = 9  =>  0 pairs (X)
A4,A7: 9.. / A4 = 9  =>  0 pairs (*) / A7 = 9  =>  0 pairs (X)
B3,B9: 9.. / B3 = 9  =>  0 pairs (X) / B9 = 9  =>  0 pairs (_)
C3,C5: 9.. / C3 = 9  =>  0 pairs (*) / C5 = 9  =>  0 pairs (X)
D1,D8: 9.. / D1 = 9  =>  0 pairs (X) / D8 = 9  =>  0 pairs (_)
G2,G7: 9.. / G2 = 9  =>  0 pairs (X) / G7 = 9  =>  0 pairs (_)
I1,I8: 9.. / I1 = 9  =>  0 pairs (*) / I8 = 9  =>  0 pairs (X)
* DURATION: 0:01:54.384267  START: 13:23:56.350476  END: 13:25:50.734743 2017-05-04
* CP COUNT: (61)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A7,B3,B5,B6,B7,B9,C3,C5,C6,C7,D1,D8,E2,E3,E4,F5,F6,G2,G7,H2,H8,I1,I3,I8)
* 365.7.14.2175.4..64..1.675..416.35275..21.4686..45.391...765.14756.412..1.43..675
* PAIR D1: 8,9 BLK 2
F1: 8,9,2                                # reduction candidate for 8,9
F1: 8,9 => CTR
* 365.7.1422175.49864..126753.416.35275..21.4686..45.3919..76581475684123918439.675
F1: 2 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
* PAIR I1: 2,9 ROW 1
F1: 2,9,8                                # reduction candidate for 2,9
F1: 2,9 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
F1: 8 => CTR
* 365.781422175.49864..126753.416835275..2194686.8457391...765.14756.412..1.43..675
* PAIR E4: 8,9 COL E
E9: 8,9,2                                # reduction candidate for 8,9
E9: 8,9 => CTR
* 3659781422175349864..126753.416835275..2194686.8457391...765.14756.412391.43.2675
E9: 2 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
* PAIR B9: 8,9 ROW 9
E9: 8,9,2                                # reduction candidate for 8,9
E9: 8,9 => CTR
* 3659781422175349864..126753.416835275..2194686.8457391...765.14756.412391.43.2675
E9: 2 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
F9: 8,9,2                                # reduction candidate for 8,9
F9: 8,9 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
F9: 2 => CTR
* 365.7.1422175.49864..126753.416.35275..21.4686..45.3919..765814756841239184392675
* PAIR D8: 8,9 BLK 8
E9: 8,9,2                                # reduction candidate for 8,9
E9: 8,9 => CTR
* 3659781422175349864..126753.416835275..2194686.8457391...765.14756.412391.43.2675
E9: 2 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
F9: 8,9,2                                # reduction candidate for 8,9
F9: 8,9 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
F9: 2 => CTR
* 365.7.1422175.49864..126753.416.35275..21.4686..45.3919..765814756841239184392675
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-305-base-pr-000.dot
* REASONING
* DIS # F1: 8,9 => CTR => F1: 2
* PRF # F1: 2 => SOL
* PRF # F1: 2,9 => SOL
* DIS # F1: 8 => CTR => F1: 2,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* CNT  14 HDP CHAINS /  14 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A7,B3,B5,B6,B7,B9,C3,C5,C6,C7,D1,D8,E2,E3,E4,F5,F6,G2,G7,H2,H8,I1,I3,I8)
* 365.7.14.2175.4..64..1.675..416.35275..21.4686..45.391...765.14756.412..1.43..675
* PAIR D1: 8,9 BLK 2
F1: 8,9,2                                # reduction candidate for 8,9
F1: 8,9 => CTR
* 365.7.1422175.49864..126753.416.35275..21.4686..45.3919..76581475684123918439.675
F1: 2 => SOLVED
* 365872149217594836489136752941683527573219468628457391832765914756941283194328675
* DURATION: 0:00:03.236102  START: 13:26:10.085289  END: 13:26:13.321391 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-305-base-pr-001.dot
* REASONING
* DIS # F1: 8,9 => CTR => F1: 2
* PRF F1: 2 => SOL
* STA F1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 305

solution: 365872149217594836489136752941683527573219468628457391832765914756941283194328675
info: 2592     FNBTWX   S8.f     30082

http://www.sfsudoku.com/su17ExtremeDiff500.txt from http://www.minimumsudoku.com/

Solution

position: 365872149217594836489136752941683527573219468628457391832765914756941283194328675 solved
Solution

See section Pair Reduction for the HDP chains leading to this result.

Appendix: Full HDP Chains

A1. Pair Reduction Analysis

Full list of HDP chains traversed:

* DIS # F1: 8,9 => CTR => F1: 2
* PRF # F1: 2 => SOL
* PRF # F1: 2,9 => SOL
* DIS # F1: 8 => CTR => F1: 2,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* DIS # E9: 8,9 => CTR => E9: 2
* PRF # E9: 2 => SOL
* PRF # F9: 8,9 => SOL
* DIS # F9: 2 => CTR => F9: 8,9
* CNT  14 HDP CHAINS /  14 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # F1: 8,9 => CTR => F1: 2
* PRF F1: 2 => SOL
* STA F1: 2
* CNT   2 HDP CHAINS /   1 HYP OPENED