Analysis of xx-top500-380-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 4..6..5.783..............1...8.91...2.....4......8.......4..3....1.......9....... initial

Autosolve

position: 41263859783.1.92649...42813.48.91.3.2.93..4811.3.849...8.41.329.219...48.9482.1.. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # C3: 5,7 => SOL
* PRF # C7: 6 => SOL
* PRF # C3: 5,7 => SOL
* PRF # B6: 5,7 => SOL
* PRF # B3: 6 => SOL
* DIS # A4: 5 => CTR => A4: 6,7
* PRF # B6: 5,7 => SOL
* DIS # A8: 6,7 => CTR => A8: 3,5
* DIS # F8: 6,7 => CTR => F8: 3,5
* CNT   9 HDP CHAINS /  31 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 # C3: 5,7 => SOL
* STA C3: 5,7
* CNT   1 HDP CHAINS /   2 HYP OPENED

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

Details

Positions

4..6..5.783..............1...8.91...2.....4......8.......4..3....1.......9....... initial
41263859783.1.92649...42813.48.91.3.2.93..4811.3.849...8.41.329.219...48.9482.1.. autosolve
412638597837159264965742813648591732259367481173284956786415329521973648394826175 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (9)
C2: 5,7
E2: 5,7
D3: 5,7
B5: 5,7
G4: 6,7
H6: 5,7
G8: 6,7
H9: 5,7
I9: 5,6

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
D4,D6: 2.. / D4 = 2  => 14 pairs (_) / D6 = 2  => 12 pairs (_)
I4,I6: 2.. / I4 = 2  => 12 pairs (_) / I6 = 2  => 14 pairs (_)
D4,I4: 2.. / D4 = 2  => 14 pairs (_) / I4 = 2  => 12 pairs (_)
D6,I6: 2.. / D6 = 2  => 12 pairs (_) / I6 = 2  => 14 pairs (_)
A8,A9: 3.. / A8 = 3  => 11 pairs (_) / A9 = 3  => 10 pairs (_)
F8,F9: 3.. / F8 = 3  => 10 pairs (_) / F9 = 3  => 11 pairs (_)
A8,F8: 3.. / A8 = 3  => 11 pairs (_) / F8 = 3  => 10 pairs (_)
A9,F9: 3.. / A9 = 3  => 10 pairs (_) / F9 = 3  => 11 pairs (_)
E2,D3: 5.. / E2 = 5  =>  0 pairs (*) / D3 = 5  =>  0 pairs (X)
H9,I9: 5.. / H9 = 5  => 14 pairs (_) / I9 = 5  => 16 pairs (_)
C2,E2: 5.. / C2 = 5  =>  0 pairs (X) / E2 = 5  =>  0 pairs (_)
H6,H9: 5.. / H6 = 5  => 16 pairs (_) / H9 = 5  => 14 pairs (_)
B3,C3: 6.. / B3 = 6  =>  0 pairs (*) / C3 = 6  =>  0 pairs (X)
A4,B6: 6.. / A4 = 6  =>  0 pairs (*) / B6 = 6  =>  0 pairs (X)
E5,F5: 6.. / E5 = 6  => 11 pairs (_) / F5 = 6  => 16 pairs (_)
G8,I9: 6.. / G8 = 6  => 16 pairs (_) / I9 = 6  => 14 pairs (_)
B6,I6: 6.. / B6 = 6  => 13 pairs (_) / I6 = 6  =>  0 pairs (*)
B3,B6: 6.. / B3 = 6  =>  0 pairs (*) / B6 = 6  =>  0 pairs (X)
C3,C7: 6.. / C3 = 6  => 13 pairs (_) / C7 = 6  =>  0 pairs (*)
E5,E8: 6.. / E5 = 6  => 11 pairs (_) / E8 = 6  => 16 pairs (_)
G4,G8: 6.. / G4 = 6  => 14 pairs (_) / G8 = 6  => 16 pairs (_)
E2,D3: 7.. / E2 = 7  =>  0 pairs (X) / D3 = 7  =>  0 pairs (_)
G4,H6: 7.. / G4 = 7  => 16 pairs (_) / H6 = 7  => 14 pairs (_)
G8,H9: 7.. / G8 = 7  => 14 pairs (_) / H9 = 7  => 16 pairs (_)
C2,E2: 7.. / C2 = 7  =>  0 pairs (*) / E2 = 7  =>  0 pairs (X)
G4,G8: 7.. / G4 = 7  => 16 pairs (_) / G8 = 7  => 14 pairs (_)
H6,H9: 7.. / H6 = 7  => 14 pairs (_) / H9 = 7  => 16 pairs (_)
* DURATION: 0:00:48.326246  START: 15:51:50.740170  END: 15:52:39.066416 2017-05-04
* CP COUNT: (27)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B5,C2,D3,E2,G4,G8,H6,H9,I9)
* 41263859783.1.92649...42813.48.91.3.2.93..4811.3.849...8.41.329.219...48.9482.1..
* PAIR C2: 5,7 BLK 1
B3: 5,7,6                                # reduction candidate for 5,7
B3: 5,7                                  # 13 pairs
C3: 5,7,6                                # reduction candidate for 5,7
C3: 5,7 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
C3: 6                                    # 13 pairs
* PAIR C2: 5,7 COL C
C7: 5,7,6                                # reduction candidate for 5,7
C7: 6 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
C7: 5,7                                  # 13 pairs
* PAIR E2: 5,7 COL E
E5: 5,7,6                                # reduction candidate for 5,7
E5: 5,7                                  # 16 pairs
E8: 5,7,6                                # reduction candidate for 5,7
E8: 5,7                                  # 11 pairs
* PAIR D3: 5,7 ROW 3
B3: 5,7,6                                # reduction candidate for 5,7
B3: 5,7                                  # 13 pairs
C3: 5,7,6                                # reduction candidate for 5,7
C3: 5,7 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
C3: 6                                    # 13 pairs
* PAIR D3: 5,7 COL D
D4: 5,7,2                                # reduction candidate for 5,7
D4: 5,7                                  # 12 pairs
D6: 5,7,2                                # reduction candidate for 5,7
D6: 5,7                                  # 14 pairs
* PAIR B5: 5,7 BLK 4
A4: 5,7,6                                # reduction candidate for 5,7
A4: 5,7                                  # 13 pairs
B6: 5,7,6                                # reduction candidate for 5,7
B6: 5,7 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
B6: 6                                    # 13 pairs
* PAIR B5: 5,7 ROW 5
E5: 5,7,6                                # reduction candidate for 5,7
E5: 5,7                                  # 16 pairs
F5: 5,7,6                                # reduction candidate for 5,7
F5: 5,7                                  # 11 pairs
* PAIR B5: 5,7 COL B
B3: 5,7,6                                # reduction candidate for 5,7
B3: 6 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
B3: 5,7                                  # 13 pairs
* PAIR G4: 6,7 ROW 4
A4: 6,7,5                                # reduction candidate for 6,7
A4: 5 => CTR
* 412638597837159264956742813548291736279365481163.849...8541.329.219...48.9482.1..
A4: 6,7                                  # 14 pairs
* PAIR H6: 5,7 ROW 6
B6: 5,7,6                                # reduction candidate for 5,7
B6: 5,7 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
B6: 6                                    # 13 pairs
D6: 5,7,2                                # reduction candidate for 5,7
D6: 5,7                                  # 14 pairs
* PAIR G8: 6,7 ROW 8
A8: 6,7,3,5                              # reduction candidate for 6,7
A8: 6,7 => CTR
* 4126385978351792649..542813.48.91.3.2.9365481153.84976.8.41.329.21953.4839482.1..
A8: 3,5                                  # 10 pairs
E8: 6,7,5                                # reduction candidate for 6,7
E8: 6,7                                  # 13 pairs
F8: 6,7,3,5                              # reduction candidate for 6,7
F8: 6,7 => CTR
* 4126385978351792649..542813.48.91.3.2.9365481153.84976.8.41.32932195..48.948231..
F8: 3,5                                  # 10 pairs
* PAIR I9: 5,6 COL I
I4: 5,6,2                                # reduction candidate for 5,6
I4: 5,6                                  # 14 pairs
I6: 5,6,2                                # reduction candidate for 5,6
I6: 5,6                                  # 12 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-380-base-pr-000.dot
* REASONING
* PRF # C3: 5,7 => SOL
* PRF # C7: 6 => SOL
* PRF # C3: 5,7 => SOL
* PRF # B6: 5,7 => SOL
* PRF # B3: 6 => SOL
* DIS # A4: 5 => CTR => A4: 6,7
* PRF # B6: 5,7 => SOL
* DIS # A8: 6,7 => CTR => A8: 3,5
* DIS # F8: 6,7 => CTR => F8: 3,5
* CNT   9 HDP CHAINS /  31 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (B5,C2,D3,E2,G4,G8,H6,H9,I9)
* 41263859783.1.92649...42813.48.91.3.2.93..4811.3.849...8.41.329.219...48.9482.1..
* PAIR C2: 5,7 BLK 1
B3: 5,7,6                                # reduction candidate for 5,7
B3: 5,7                                  # 13 pairs
C3: 5,7,6                                # reduction candidate for 5,7
C3: 5,7 => SOLVED
* 412638597837159264965742813648591732259367481173284956786415329521973648394826175
* DURATION: 0:00:02.968964  START: 15:53:10.725171  END: 15:53:13.694135 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-380-base-pr-001.dot
* REASONING
* PRF # C3: 5,7 => SOL
* STA C3: 5,7
* CNT   1 HDP CHAINS /   2 HYP OPENED

Header Info

Top 500 Minimum 17 380

solution: 412638597837159264965742813648591732259367481173284956786415329521973648394826175
info: 32793    FNBO     S8.f     39511

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

Solution

position: 412638597837159264965742813648591732259367481173284956786415329521973648394826175 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 # B3: 5,7 => UNS
* PRF # C3: 5,7 => SOL
* INC # C3: 6 => UNS
* INC # C7: 5,7 => UNS
* PRF # C7: 6 => SOL
* INC # E5: 5,7 => UNS
* INC # E8: 5,7 => UNS
* INC # B3: 5,7 => UNS
* PRF # C3: 5,7 => SOL
* INC # C3: 6 => UNS
* INC # D4: 5,7 => UNS
* INC # D6: 5,7 => UNS
* INC # A4: 5,7 => UNS
* PRF # B6: 5,7 => SOL
* INC # B6: 6 => UNS
* INC # E5: 5,7 => UNS
* INC # F5: 5,7 => UNS
* INC # B3: 5,7 => UNS
* PRF # B3: 6 => SOL
* INC # A4: 6,7 => UNS
* DIS # A4: 5 => CTR => A4: 6,7
* PRF # B6: 5,7 => SOL
* INC # B6: 6 => UNS
* INC # D6: 5,7 => UNS
* DIS # A8: 6,7 => CTR => A8: 3,5
* INC # A8: 3,5 => UNS
* INC # E8: 6,7 => UNS
* DIS # F8: 6,7 => CTR => F8: 3,5
* INC # F8: 3,5 => UNS
* INC # I4: 5,6 => UNS
* INC # I6: 5,6 => UNS
* CNT  31 HDP CHAINS /  31 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # B3: 5,7 => UNS
* PRF # C3: 5,7 => SOL
* STA C3: 5,7
* CNT   2 HDP CHAINS /   2 HYP OPENED