Analysis of xx-top500-131-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 1.4...2..6..5...3...........3.....582...14................2.1...5.8.....7........ initial

Autosolve

position: 1.4.832.56.854..315.31..84..312...58285.14....67.58.1284..251.335.8.1.2471243.58. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # H1: 7,9 => SOL
* PRF # H1: 7,9 => SOL
* DIS # G4: 7,9 => CTR => G4: 4,6
* DIS # G5: 7,9 => CTR => G5: 3,6
* CNT   4 HDP CHAINS /  35 HYP OPENED

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

Pair Reduction

Pair Reduction

The following important HDP chains were detected:

* PRF # H1: 7,9 => SOL
* STA H1: 7,9
* CNT   1 HDP CHAINS /   4 HYP OPENED

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

Details

Positions

1.4...2..6..5...3...........3.....582...14................2.1...5.8.....7........ initial
1.4.832.56.854..315.31..84..312...58285.14....67.58.1284..251.335.8.1.2471243.58. autosolve
194683275678542931523179846931267458285314697467958312849725163356891724712436589 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (9)
B1: 7,9
G2: 7,9
A4: 4,9
A6: 4,9
D6: 3,9
C7: 6,9
C8: 6,9
F9: 6,9
I9: 6,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B2,B3: 2.. / B2 = 2  => 11 pairs (_) / B3 = 2  => 10 pairs (_)
F2,F3: 2.. / F2 = 2  => 10 pairs (_) / F3 = 2  => 11 pairs (_)
B2,F2: 2.. / B2 = 2  => 11 pairs (_) / F2 = 2  => 10 pairs (_)
B3,F3: 2.. / B3 = 2  => 10 pairs (_) / F3 = 2  => 11 pairs (_)
D5,D6: 3.. / D5 = 3  => 10 pairs (_) / D6 = 3  =>  9 pairs (_)
G5,G6: 3.. / G5 = 3  =>  9 pairs (_) / G6 = 3  => 10 pairs (_)
D5,G5: 3.. / D5 = 3  => 10 pairs (_) / G5 = 3  =>  9 pairs (_)
D6,G6: 3.. / D6 = 3  =>  9 pairs (_) / G6 = 3  => 10 pairs (_)
A4,A6: 4.. / A4 = 4  =>  6 pairs (_) / A6 = 4  => 13 pairs (_)
G4,G6: 4.. / G4 = 4  => 13 pairs (_) / G6 = 4  =>  6 pairs (_)
A4,G4: 4.. / A4 = 4  =>  6 pairs (_) / G4 = 4  => 13 pairs (_)
A6,G6: 4.. / A6 = 4  => 13 pairs (_) / G6 = 4  =>  6 pairs (_)
H1,I3: 6.. / H1 = 6  => 13 pairs (_) / I3 = 6  =>  0 pairs (*)
C7,C8: 6.. / C7 = 6  => 11 pairs (_) / C8 = 6  => 17 pairs (_)
D1,H1: 6.. / D1 = 6  =>  0 pairs (*) / H1 = 6  =>  0 pairs (X)
F9,I9: 6.. / F9 = 6  => 14 pairs (_) / I9 = 6  => 21 pairs (_)
D7,E8: 7.. / D7 = 7  => 21 pairs (_) / E8 = 7  => 15 pairs (_)
H7,G8: 7.. / H7 = 7  => 15 pairs (_) / G8 = 7  => 21 pairs (_)
D7,H7: 7.. / D7 = 7  => 21 pairs (_) / H7 = 7  => 15 pairs (_)
E8,G8: 7.. / E8 = 7  => 15 pairs (_) / G8 = 7  => 21 pairs (_)
I3,I5: 7.. / I3 = 7  => 18 pairs (_) / I5 = 7  => 11 pairs (_)
A4,A6: 9.. / A4 = 9  => 13 pairs (_) / A6 = 9  =>  6 pairs (_)
C7,C8: 9.. / C7 = 9  => 17 pairs (_) / C8 = 9  => 11 pairs (_)
F9,I9: 9.. / F9 = 9  => 21 pairs (_) / I9 = 9  => 14 pairs (_)
* DURATION: 0:00:37.423016  START: 07:14:25.614384  END: 07:15:03.037400 2017-05-04
* CP COUNT: (24)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A6,B1,C7,C8,D6,F9,G2,I9)
* 1.4.832.56.854..315.31..84..312...58285.14....67.58.1284..251.335.8.1.2471243.58.
* PAIR B1: 7,9 BLK 1
B2: 7,9,2                                # reduction candidate for 7,9
B2: 7,9                                  # 10 pairs
B3: 7,9,2                                # reduction candidate for 7,9
B3: 7,9                                  # 11 pairs
* PAIR B1: 7,9 ROW 1
D1: 7,9,6                                # reduction candidate for 7,9
D1: 7,9                                  # 13 pairs
H1: 7,9,6                                # reduction candidate for 7,9
H1: 7,9 => SOLVED
* 194683275678542931523179846931267458285314697467958312849725163356891724712436589
H1: 6                                    # 13 pairs
* PAIR G2: 7,9 BLK 3
H1: 7,9,6                                # reduction candidate for 7,9
H1: 7,9 => SOLVED
* 194683275678542931523179846931267458285314697467958312849725163356891724712436589
H1: 6                                    # 13 pairs
I3: 7,9,6                                # reduction candidate for 7,9
I3: 7,9                                  # 13 pairs
* PAIR G2: 7,9 ROW 2
B2: 7,9,2                                # reduction candidate for 7,9
B2: 7,9                                  # 10 pairs
F2: 7,9,2                                # reduction candidate for 7,9
F2: 7,9                                  # 11 pairs
* PAIR G2: 7,9 COL G
G4: 7,9,4,6                              # reduction candidate for 7,9
G4: 7,9 => CTR
* 1.46832956.854..315.31..84.43126..58285.143..967358412846925173359871624712436589
G4: 4,6                                  # 10 pairs
G5: 7,9,3,6                              # reduction candidate for 7,9
G5: 7,9 => CTR
* 1.4.832.56.854..315.31..84.9312..458285314...46795831284..251.335.8.1624712436589
G5: 3,6                                  # 10 pairs
G8: 7,9,6                                # reduction candidate for 7,9
G8: 7,9                                  # 16 pairs
* PAIR A4: 4,9 ROW 4
G4: 4,9,6,7                              # reduction candidate for 4,9
G4: 4,9                                  # 15 pairs
G4: 6,7                                  #  8 pairs
* PAIR A6: 4,9 ROW 6
G6: 4,9,3                                # reduction candidate for 4,9
G6: 3                                    # 10 pairs
G6: 4,9                                  #  9 pairs
* PAIR D6: 3,9 BLK 5
D5: 3,9,6,7                              # reduction candidate for 3,9
D5: 3,9                                  # 15 pairs
D5: 6,7                                  #  8 pairs
* PAIR D6: 3,9 ROW 6
G6: 3,9,4                                # reduction candidate for 3,9
G6: 3,9                                  # 13 pairs
G6: 4                                    #  6 pairs
* PAIR C7: 6,9 ROW 7
D7: 6,9,7                                # reduction candidate for 6,9
D7: 6,9                                  # 15 pairs
H7: 6,9,7                                # reduction candidate for 6,9
H7: 6,9                                  # 21 pairs
* PAIR C8: 6,9 ROW 8
E8: 6,9,7                                # reduction candidate for 6,9
E8: 6,9                                  # 21 pairs
G8: 6,9,7                                # reduction candidate for 6,9
G8: 6,9                                  # 15 pairs
* PAIR F9: 6,9 BLK 8
D7: 6,9,7                                # reduction candidate for 6,9
D7: 6,9                                  # 15 pairs
E8: 6,9,7                                # reduction candidate for 6,9
E8: 6,9                                  # 21 pairs
* PAIR F9: 6,9 COL F
F3: 6,9,2,7                              # reduction candidate for 6,9
F3: 6,9                                  # 12 pairs
F4: 6,9,7                                # reduction candidate for 6,9
F4: 6,9                                  # 14 pairs
* PAIR I9: 6,9 BLK 9
H7: 6,9,7                                # reduction candidate for 6,9
H7: 6,9                                  # 21 pairs
G8: 6,9,7                                # reduction candidate for 6,9
G8: 6,9                                  # 15 pairs
* PAIR I9: 6,9 COL I
I3: 6,9,7                                # reduction candidate for 6,9
I3: 6,9                                  # 11 pairs
I5: 6,9,7                                # reduction candidate for 6,9
I5: 6,9                                  # 18 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-131-base-pr-000.dot
* REASONING
* PRF # H1: 7,9 => SOL
* PRF # H1: 7,9 => SOL
* DIS # G4: 7,9 => CTR => G4: 4,6
* DIS # G5: 7,9 => CTR => G5: 3,6
* CNT   4 HDP CHAINS /  35 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A6,B1,C7,C8,D6,F9,G2,I9)
* 1.4.832.56.854..315.31..84..312...58285.14....67.58.1284..251.335.8.1.2471243.58.
* PAIR B1: 7,9 BLK 1
B2: 7,9,2                                # reduction candidate for 7,9
B2: 7,9                                  # 10 pairs
B3: 7,9,2                                # reduction candidate for 7,9
B3: 7,9                                  # 11 pairs
* PAIR B1: 7,9 ROW 1
D1: 7,9,6                                # reduction candidate for 7,9
D1: 7,9                                  # 13 pairs
H1: 7,9,6                                # reduction candidate for 7,9
H1: 7,9 => SOLVED
* 194683275678542931523179846931267458285314697467958312849725163356891724712436589
* DURATION: 0:00:04.356644  START: 07:15:33.594500  END: 07:15:37.951144 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-131-base-pr-001.dot
* REASONING
* PRF # H1: 7,9 => SOL
* STA H1: 7,9
* CNT   1 HDP CHAINS /   4 HYP OPENED

Header Info

Top 500 Minimum 17 131

solution: 194683275678542931523179846931267458285314697467958312849725163356891724712436589
info: 1811     FNBWXY   S8.f     26041

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

Solution

position: 194683275678542931523179846931267458285314697467958312849725163356891724712436589 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:

* INC # B2: 7,9 => UNS
* INC # B3: 7,9 => UNS
* INC # D1: 7,9 => UNS
* PRF # H1: 7,9 => SOL
* INC # H1: 6 => UNS
* PRF # H1: 7,9 => SOL
* INC # H1: 6 => UNS
* INC # I3: 7,9 => UNS
* INC # B2: 7,9 => UNS
* INC # F2: 7,9 => UNS
* DIS # G4: 7,9 => CTR => G4: 4,6
* INC # G4: 4,6 => UNS
* DIS # G5: 7,9 => CTR => G5: 3,6
* INC # G5: 3,6 => UNS
* INC # G8: 7,9 => UNS
* INC # G4: 4,9 => UNS
* INC # G4: 6,7 => UNS
* INC # G6: 4,9 => UNS
* INC # G6: 3 => UNS
* INC # D5: 3,9 => UNS
* INC # D5: 6,7 => UNS
* INC # G6: 3,9 => UNS
* INC # G6: 4 => UNS
* INC # D7: 6,9 => UNS
* INC # H7: 6,9 => UNS
* INC # E8: 6,9 => UNS
* INC # G8: 6,9 => UNS
* INC # D7: 6,9 => UNS
* INC # E8: 6,9 => UNS
* INC # F3: 6,9 => UNS
* INC # F4: 6,9 => UNS
* INC # H7: 6,9 => UNS
* INC # G8: 6,9 => UNS
* INC # I3: 6,9 => UNS
* INC # I5: 6,9 => UNS
* CNT  35 HDP CHAINS /  35 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B2: 7,9 => UNS
* INC # B3: 7,9 => UNS
* INC # D1: 7,9 => UNS
* PRF # H1: 7,9 => SOL
* STA H1: 7,9
* CNT   4 HDP CHAINS /   4 HYP OPENED