Analysis of xx-top500-149-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .87.4........7..1....6.....3..1.2...5.....7.4......8..1..3......5....4........... initial

Autosolve

position: .875413.24.527..18..16.8547374182.5.5189..724...75483114.3.728575281.4.38.342517. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # A6: 2 => CTR => A6: 6,9
* DIS # B3: 2,9 => CTR => B3: 3
* PRF # B3: 3 => SOL
* PRF # A6: 2,9 => SOL
* DIS # A6: 6 => CTR => A6: 2,9
* PRF # B2: 3,9 => SOL
* DIS # B2: 6 => CTR => B2: 3,9
* DIS # B3: 2 => CTR => B3: 3,9
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # B6: 6,9 => CTR => B6: 2
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # B6: 6,9 => CTR => B6: 2
* CNT  16 HDP CHAINS /  21 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 # B2: 6,9 => SOL
* STA B2: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

.87.4........7..1....6.....3..1.2...5.....7.4......8..1..3......5....4........... initial
.875413.24.527..18..16.8547374182.5.5189..724...75483114.3.728575281.4.38.342517. autosolve
687541392495273618231698547374182956518936724926754831149367285752819463863425179 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (17)
A1: 6,9
A3: 2,9
F2: 3,9
E3: 3,9
H1: 6,9
G2: 6,9
C6: 6,9
E5: 3,6
F5: 3,6
G4: 6,9
I4: 6,9
C7: 6,9
B9: 6,9
E7: 6,9
F8: 6,9
H8: 6,9
I9: 6,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
A3,B3: 2.. / A3 = 2  => 18 pairs (_) / B3 = 2  =>  0 pairs (X)
A6,B6: 2.. / A6 = 2  =>  0 pairs (X) / B6 = 2  => 18 pairs (_)
A3,A6: 2.. / A3 = 2  => 18 pairs (_) / A6 = 2  =>  0 pairs (X)
B3,B6: 2.. / B3 = 2  =>  0 pairs (X) / B6 = 2  => 18 pairs (_)
B2,B3: 3.. / B2 = 3  =>  0 pairs (X) / B3 = 3  =>  0 pairs (_)
F2,E3: 3.. / F2 = 3  =>  0 pairs (*) / E3 = 3  =>  0 pairs (X)
E5,F5: 3.. / E5 = 3  =>  0 pairs (*) / F5 = 3  =>  0 pairs (X)
B2,F2: 3.. / B2 = 3  =>  0 pairs (X) / F2 = 3  =>  0 pairs (_)
B3,E3: 3.. / B3 = 3  =>  0 pairs (*) / E3 = 3  =>  0 pairs (X)
E3,E5: 3.. / E3 = 3  =>  0 pairs (X) / E5 = 3  =>  0 pairs (_)
F2,F5: 3.. / F2 = 3  =>  0 pairs (*) / F5 = 3  =>  0 pairs (X)
A1,B2: 6.. / A1 = 6  =>  0 pairs (*) / B2 = 6  =>  0 pairs (X)
H1,G2: 6.. / H1 = 6  =>  0 pairs (X) / G2 = 6  =>  0 pairs (_)
E5,F5: 6.. / E5 = 6  =>  0 pairs (X) / F5 = 6  =>  0 pairs (_)
G4,I4: 6.. / G4 = 6  =>  0 pairs (X) / I4 = 6  =>  0 pairs (_)
C7,B9: 6.. / C7 = 6  =>  0 pairs (X) / B9 = 6  =>  0 pairs (_)
E7,F8: 6.. / E7 = 6  =>  0 pairs (*) / F8 = 6  =>  0 pairs (X)
H8,I9: 6.. / H8 = 6  =>  0 pairs (*) / I9 = 6  =>  0 pairs (X)
A1,H1: 6.. / A1 = 6  =>  0 pairs (*) / H1 = 6  =>  0 pairs (X)
B2,G2: 6.. / B2 = 6  =>  0 pairs (X) / G2 = 6  =>  0 pairs (_)
C7,E7: 6.. / C7 = 6  =>  0 pairs (X) / E7 = 6  =>  0 pairs (_)
F8,H8: 6.. / F8 = 6  =>  0 pairs (X) / H8 = 6  =>  0 pairs (_)
B9,I9: 6.. / B9 = 6  =>  0 pairs (*) / I9 = 6  =>  0 pairs (X)
A1,A6: 6.. / A1 = 6  =>  0 pairs (*) / A6 = 6  =>  0 pairs (X)
C6,C7: 6.. / C6 = 6  =>  0 pairs (*) / C7 = 6  =>  0 pairs (X)
E5,E7: 6.. / E5 = 6  =>  0 pairs (X) / E7 = 6  =>  0 pairs (_)
F5,F8: 6.. / F5 = 6  =>  0 pairs (*) / F8 = 6  =>  0 pairs (X)
G2,G4: 6.. / G2 = 6  =>  0 pairs (*) / G4 = 6  =>  0 pairs (X)
H1,H8: 6.. / H1 = 6  =>  0 pairs (X) / H8 = 6  =>  0 pairs (_)
I4,I9: 6.. / I4 = 6  =>  0 pairs (*) / I9 = 6  =>  0 pairs (X)
F2,E3: 9.. / F2 = 9  =>  0 pairs (X) / E3 = 9  =>  0 pairs (_)
H1,G2: 9.. / H1 = 9  =>  0 pairs (*) / G2 = 9  =>  0 pairs (X)
G4,I4: 9.. / G4 = 9  =>  0 pairs (*) / I4 = 9  =>  0 pairs (X)
C7,B9: 9.. / C7 = 9  =>  0 pairs (*) / B9 = 9  =>  0 pairs (X)
E7,F8: 9.. / E7 = 9  =>  0 pairs (X) / F8 = 9  =>  0 pairs (_)
H8,I9: 9.. / H8 = 9  =>  0 pairs (X) / I9 = 9  =>  0 pairs (_)
A1,H1: 9.. / A1 = 9  =>  0 pairs (X) / H1 = 9  =>  0 pairs (_)
C7,E7: 9.. / C7 = 9  =>  0 pairs (*) / E7 = 9  =>  0 pairs (X)
F8,H8: 9.. / F8 = 9  =>  0 pairs (*) / H8 = 9  =>  0 pairs (X)
B9,I9: 9.. / B9 = 9  =>  0 pairs (X) / I9 = 9  =>  0 pairs (_)
C6,C7: 9.. / C6 = 9  =>  0 pairs (X) / C7 = 9  =>  0 pairs (_)
E3,E7: 9.. / E3 = 9  =>  0 pairs (*) / E7 = 9  =>  0 pairs (X)
F2,F8: 9.. / F2 = 9  =>  0 pairs (X) / F8 = 9  =>  0 pairs (_)
G2,G4: 9.. / G2 = 9  =>  0 pairs (X) / G4 = 9  =>  0 pairs (_)
H1,H8: 9.. / H1 = 9  =>  0 pairs (*) / H8 = 9  =>  0 pairs (X)
I4,I9: 9.. / I4 = 9  =>  0 pairs (X) / I9 = 9  =>  0 pairs (_)
* DURATION: 0:01:22.476165  START: 07:50:13.809595  END: 07:51:36.285760 2017-05-04
* CP COUNT: (46)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,B9,C6,C7,E3,E5,E7,F2,F5,F8,G2,G4,H1,H8,I4,I9)
* .875413.24.527..18..16.8547374182.5.5189..724...75483114.3.728575281.4.38.342517.
* PAIR A1: 6,9 BLK 1
B2: 6,9,3                                # reduction candidate for 6,9
B2: 6,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
B2: 3 => CTR
* 687541392435279618..1638547374182956518963724...7548311463972857528164.38.342517.
* PAIR A1: 6,9 COL A
A6: 6,9,2                                # reduction candidate for 6,9
A6: 2 => CTR
* 6875413924.527.618921638547374182956518963724...75483114.3.728575281.4.38.342517.
A6: 6,9                                  # 18 pairs
* PAIR A3: 2,9 BLK 1
B3: 2,9,3                                # reduction candidate for 2,9
B3: 2,9 => CTR
* .875413.2435279618..1638547374182956518963724...7548311463972857528164.38.342517.
B3: 3 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
* PAIR A3: 2,9 COL A
A6: 2,9,6                                # reduction candidate for 2,9
A6: 2,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
A6: 6 => CTR
* .875413.24.527..182.16.8547374182.5.5189..724629754831146397285752816493893425176
* PAIR F2: 3,9 ROW 2
B2: 3,9,6                                # reduction candidate for 3,9
B2: 3,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
B2: 6 => CTR
* .875413.2465273918.3169854737418265951893672462975483114.3.728575281.4.38.342517.
* PAIR E3: 3,9 ROW 3
B3: 3,9,2                                # reduction candidate for 3,9
B3: 2 => CTR
* .875413.24352796189216385473741829565189637242..7548311463972857528164.38.342517.
B3: 3,9                                  # 18 pairs
* PAIR G2: 6,9 ROW 2
B2: 6,9,3                                # reduction candidate for 6,9
B2: 6,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
B2: 3 => CTR
* 687541392435279618..1638547374182956518963724...7548311463972857528164.38.342517.
* PAIR C6: 6,9 BLK 4
A6: 6,9,2                                # reduction candidate for 6,9
A6: 6,9                                  # 18 pairs
B6: 6,9,2                                # reduction candidate for 6,9
B6: 6,9 => CTR
* .875413.24.527..18.21638547374182.5.5189637242..754831146397285752816493893425176
B6: 2                                    # 18 pairs
* PAIR B9: 6,9 COL B
B2: 6,9,3                                # reduction candidate for 6,9
B2: 6,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
B2: 3 => CTR
* 687541392435279618..1638547374182956518963724...7548311463972857528164.38.342517.
B6: 6,9,2                                # reduction candidate for 6,9
B6: 6,9 => CTR
* .875413.24.527..18.21638547374182.5.5189637242..754831146397285752816493893425176
B6: 2                                    # 18 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-149-base-pr-000.dot
* REASONING
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # A6: 2 => CTR => A6: 6,9
* DIS # B3: 2,9 => CTR => B3: 3
* PRF # B3: 3 => SOL
* PRF # A6: 2,9 => SOL
* DIS # A6: 6 => CTR => A6: 2,9
* PRF # B2: 3,9 => SOL
* DIS # B2: 6 => CTR => B2: 3,9
* DIS # B3: 2 => CTR => B3: 3,9
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # B6: 6,9 => CTR => B6: 2
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # B6: 6,9 => CTR => B6: 2
* CNT  16 HDP CHAINS /  21 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A1,A3,B9,C6,C7,E3,E5,E7,F2,F5,F8,G2,G4,H1,H8,I4,I9)
* .875413.24.527..18..16.8547374182.5.5189..724...75483114.3.728575281.4.38.342517.
* PAIR A1: 6,9 BLK 1
B2: 6,9,3                                # reduction candidate for 6,9
B2: 6,9 => SOLVED
* 687541392495273618231698547374182956518936724926754831149367285752819463863425179
* DURATION: 0:00:01.962699  START: 07:52:03.857667  END: 07:52:05.820366 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-149-base-pr-001.dot
* REASONING
* PRF # B2: 6,9 => SOL
* STA B2: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 149

solution: 687541392495273618231698547374182956518936724926754831149367285752819463863425179
info: 1816     FNBWX    S8.f     24270

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

Solution

position: 687541392495273618231698547374182956518936724926754831149367285752819463863425179 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:

* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* INC # A6: 6,9 => UNS
* DIS # A6: 2 => CTR => A6: 6,9
* DIS # B3: 2,9 => CTR => B3: 3
* PRF # B3: 3 => SOL
* PRF # A6: 2,9 => SOL
* DIS # A6: 6 => CTR => A6: 2,9
* PRF # B2: 3,9 => SOL
* DIS # B2: 6 => CTR => B2: 3,9
* INC # B3: 3,9 => UNS
* DIS # B3: 2 => CTR => B3: 3,9
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* INC # A6: 6,9 => UNS
* DIS # B6: 6,9 => CTR => B6: 2
* INC # B6: 2 => UNS
* PRF # B2: 6,9 => SOL
* DIS # B2: 3 => CTR => B2: 6,9
* DIS # B6: 6,9 => CTR => B6: 2
* INC # B6: 2 => UNS
* CNT  21 HDP CHAINS /  21 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # B2: 6,9 => SOL
* STA B2: 6,9
* CNT   1 HDP CHAINS /   1 HYP OPENED