Analysis of xx-top500-122-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 1.8.....6...7.34............4....57.5...1...........3..7.5.........8...12........ initial

Autosolve

position: 138.5.7.6.5.7.34187.41683.53418.657.5.731.68..8..7513.879541263463287951215639847 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I5: 2,4 => SOL
* DIS # I5: 9 => CTR => I5: 2,4
* PRF # I6: 4,9 => SOL
* DIS # I6: 2 => CTR => I6: 4,9
* DIS # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I6: 2,9 => SOL
* DIS # I6: 4 => CTR => I6: 2,9
* CNT  10 HDP CHAINS /  10 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 # I5: 2,9 => CTR => I5: 4
* PRF I5: 4 => SOL
* STA I5: 4
* CNT   2 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

1.8.....6...7.34............4....57.5...1...........3..7.5.........8...12........ initial
138.5.7.6.5.7.34187.41683.53418.657.5.731.68..8..7513.879541263463287951215639847 autosolve
138954726956723418724168395341896572597312684682475139879541263463287951215639847 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (15)
A2: 6,9
C2: 2,6
B3: 2,9
D1: 4,9
F1: 2,4
E2: 2,9
H1: 2,9
H3: 2,9
B5: 2,9
A6: 6,9
C6: 2,6
E4: 2,9
F5: 2,4
D6: 4,9
I4: 2,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C2,B3: 2.. / C2 = 2  =>  0 pairs (X) / B3 = 2  =>  0 pairs (_)
F1,E2: 2.. / F1 = 2  =>  0 pairs (X) / E2 = 2  =>  0 pairs (_)
H1,H3: 2.. / H1 = 2  =>  0 pairs (*) / H3 = 2  =>  0 pairs (X)
B5,C6: 2.. / B5 = 2  =>  0 pairs (X) / C6 = 2  =>  0 pairs (_)
E4,F5: 2.. / E4 = 2  =>  0 pairs (X) / F5 = 2  =>  0 pairs (_)
F1,H1: 2.. / F1 = 2  =>  0 pairs (X) / H1 = 2  =>  0 pairs (_)
C2,E2: 2.. / C2 = 2  =>  0 pairs (X) / E2 = 2  =>  0 pairs (_)
B3,H3: 2.. / B3 = 2  =>  0 pairs (*) / H3 = 2  =>  0 pairs (X)
E4,I4: 2.. / E4 = 2  =>  0 pairs (X) / I4 = 2  =>  0 pairs (_)
C6,I6: 2.. / C6 = 2  =>  0 pairs (*) / I6 = 2  =>  0 pairs (X)
B3,B5: 2.. / B3 = 2  =>  0 pairs (*) / B5 = 2  =>  0 pairs (X)
C2,C6: 2.. / C2 = 2  =>  0 pairs (X) / C6 = 2  =>  0 pairs (_)
E2,E4: 2.. / E2 = 2  =>  0 pairs (*) / E4 = 2  =>  0 pairs (X)
F1,F5: 2.. / F1 = 2  =>  0 pairs (X) / F5 = 2  =>  0 pairs (_)
D1,F1: 4.. / D1 = 4  =>  0 pairs (X) / F1 = 4  =>  0 pairs (_)
F5,D6: 4.. / F5 = 4  =>  0 pairs (X) / D6 = 4  =>  0 pairs (_)
I5,I6: 4.. / I5 = 4  =>  0 pairs (*) / I6 = 4  =>  0 pairs (X)
F5,I5: 4.. / F5 = 4  =>  0 pairs (X) / I5 = 4  =>  0 pairs (_)
D6,I6: 4.. / D6 = 4  =>  0 pairs (*) / I6 = 4  =>  0 pairs (X)
D1,D6: 4.. / D1 = 4  =>  0 pairs (X) / D6 = 4  =>  0 pairs (_)
F1,F5: 4.. / F1 = 4  =>  0 pairs (*) / F5 = 4  =>  0 pairs (X)
A2,C2: 6.. / A2 = 6  =>  0 pairs (X) / C2 = 6  =>  0 pairs (_)
A6,C6: 6.. / A6 = 6  =>  0 pairs (*) / C6 = 6  =>  0 pairs (X)
A2,A6: 6.. / A2 = 6  =>  0 pairs (X) / A6 = 6  =>  0 pairs (_)
C2,C6: 6.. / C2 = 6  =>  0 pairs (*) / C6 = 6  =>  0 pairs (X)
A2,B3: 9.. / A2 = 9  =>  0 pairs (*) / B3 = 9  =>  0 pairs (X)
D1,E2: 9.. / D1 = 9  =>  0 pairs (*) / E2 = 9  =>  0 pairs (X)
H1,H3: 9.. / H1 = 9  =>  0 pairs (X) / H3 = 9  =>  0 pairs (_)
B5,A6: 9.. / B5 = 9  =>  0 pairs (*) / A6 = 9  =>  0 pairs (X)
E4,D6: 9.. / E4 = 9  =>  0 pairs (*) / D6 = 9  =>  0 pairs (X)
D1,H1: 9.. / D1 = 9  =>  0 pairs (*) / H1 = 9  =>  0 pairs (X)
A2,E2: 9.. / A2 = 9  =>  0 pairs (*) / E2 = 9  =>  0 pairs (X)
B3,H3: 9.. / B3 = 9  =>  0 pairs (X) / H3 = 9  =>  0 pairs (_)
E4,I4: 9.. / E4 = 9  =>  0 pairs (*) / I4 = 9  =>  0 pairs (X)
B5,I5: 9.. / B5 = 9  =>  0 pairs (*) / I5 = 9  =>  0 pairs (X)
A2,A6: 9.. / A2 = 9  =>  0 pairs (*) / A6 = 9  =>  0 pairs (X)
B3,B5: 9.. / B3 = 9  =>  0 pairs (X) / B5 = 9  =>  0 pairs (_)
D1,D6: 9.. / D1 = 9  =>  0 pairs (*) / D6 = 9  =>  0 pairs (X)
E2,E4: 9.. / E2 = 9  =>  0 pairs (X) / E4 = 9  =>  0 pairs (_)
* DURATION: 0:01:04.854525  START: 06:56:33.979423  END: 06:57:38.833948 2017-05-04
* CP COUNT: (39)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A6,B3,B5,C2,C6,D1,D6,E2,E4,F1,F5,H1,H3,I4)
* 138.5.7.6.5.7.34187.41683.53418.657.5.731.68..8..7513.879541263463287951215639847
* PAIR B5: 2,9 ROW 5
I5: 2,9,4                                # reduction candidate for 2,9
I5: 2,9 => CTR
* 13845279695.7.34187.41683.53418.657.5.731468..8.975134879541263463287951215639847
I5: 4 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
* PAIR F5: 2,4 ROW 5
I5: 2,4,9                                # reduction candidate for 2,4
I5: 2,4 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
I5: 9 => CTR
* 138.5.7.6.5.7.34187.41683.53418.657.5.731468998..7513.879541263463287951215639847
* PAIR D6: 4,9 ROW 6
I6: 4,9,2                                # reduction candidate for 4,9
I6: 4,9 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
I6: 2 => CTR
* 138.5.7.6.5.7.34187.41683.53418.657.5.731.684.8.475132879541263463287951215639847
* PAIR I4: 2,9 BLK 6
I5: 2,9,4                                # reduction candidate for 2,9
I5: 2,9 => CTR
* 13845279695.7.34187.41683.53418.657.5.731468..8.975134879541263463287951215639847
I5: 4 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
I6: 2,9,4                                # reduction candidate for 2,9
I6: 2,9 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
I6: 4 => CTR
* 1384527.6.5.7.34187.41683.53418.657.5.731.68..82.75134879541263463287951215639847
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-122-base-pr-000.dot
* REASONING
* DIS # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I5: 2,4 => SOL
* DIS # I5: 9 => CTR => I5: 2,4
* PRF # I6: 4,9 => SOL
* DIS # I6: 2 => CTR => I6: 4,9
* DIS # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I6: 2,9 => SOL
* DIS # I6: 4 => CTR => I6: 2,9
* CNT  10 HDP CHAINS /  10 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A6,B3,B5,C2,C6,D1,D6,E2,E4,F1,F5,H1,H3,I4)
* 138.5.7.6.5.7.34187.41683.53418.657.5.731.68..8..7513.879541263463287951215639847
* PAIR B5: 2,9 ROW 5
I5: 2,9,4                                # reduction candidate for 2,9
I5: 2,9 => CTR
* 13845279695.7.34187.41683.53418.657.5.731468..8.975134879541263463287951215639847
I5: 4 => SOLVED
* 138954726956723418724168395341896572597312684682475139879541263463287951215639847
* DURATION: 0:00:03.144498  START: 06:57:51.292948  END: 06:57:54.437446 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-122-base-pr-001.dot
* REASONING
* DIS # I5: 2,9 => CTR => I5: 4
* PRF I5: 4 => SOL
* STA I5: 4
* CNT   2 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 122

solution: 138954726956723418724168395341896572597312684682475139879541263463287951215639847
info: 1805     FNWX     S8.f     26234

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

Solution

position: 138954726956723418724168395341896572597312684682475139879541263463287951215639847 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 # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I5: 2,4 => SOL
* DIS # I5: 9 => CTR => I5: 2,4
* PRF # I6: 4,9 => SOL
* DIS # I6: 2 => CTR => I6: 4,9
* DIS # I5: 2,9 => CTR => I5: 4
* PRF # I5: 4 => SOL
* PRF # I6: 2,9 => SOL
* DIS # I6: 4 => CTR => I6: 2,9
* CNT  10 HDP CHAINS /  10 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # I5: 2,9 => CTR => I5: 4
* PRF I5: 4 => SOL
* STA I5: 4
* CNT   2 HDP CHAINS /   1 HYP OPENED