Analysis of xx-top500-201-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: .8.....9.4...3..............9.8...6..5..4......1......2.....3.4...5..2..3..9..... initial

Autosolve

position: 5832..49.41..3982592.4...3.7948.2.6365234.9..831.9..422691..354148563279375924... autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # I3: 6,7 => CTR => I3: 1
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* DIS # I3: 6,7 => CTR => I3: 1
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* DIS # I5: 8 => CTR => I5: 1,7
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F6: 6,7 => SOL
* DIS # F6: 5 => CTR => F6: 6,7
* DIS # I5: 1,8 => CTR => I5: 7
* PRF # I5: 7 => SOL
* DIS # F6: 5,7 => CTR => F6: 6
* PRF # F6: 6 => SOL
* DIS # I9: 1,6 => CTR => I9: 8
* DIS # G3: 1,6 => CTR => G3: 7
* PRF # G3: 7 => SOL
* DIS # I9: 6 => CTR => I9: 1,8
* CNT  21 HDP CHAINS /  28 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 # I3: 6,7 => CTR => I3: 1
* PRF I3: 1 # F1: 1,7 => SOL
* STA I3: 1 + F1: 1,7
* CNT   2 HDP CHAINS /   3 HYP OPENED

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

Details

Positions

.8.....9.4...3..............9.8...6..5..4......1......2.....3.4...5..2..3..9..... initial
5832..49.41..3982592.4...3.7948.2.6365234.9..831.9..422691..354148563279375924... autosolve
583217496417639825926485731794852163652341987831796542269178354148563279375924618 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (17)
C2: 6,7
C3: 6,7
E1: 1,7
D2: 6,7
E3: 5,8
F3: 5,8
I1: 6,7
E4: 1,5
F5: 1,7
D6: 6,7
G4: 1,5
H5: 1,8
G6: 5,7
E7: 7,8
F7: 7,8
G9: 1,6
H9: 1,8

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E1,F1: 1.. / E1 = 1  =>  0 pairs (*) / F1 = 1  =>  0 pairs (X)
G3,I3: 1.. / G3 = 1  =>  0 pairs (X) / I3 = 1  => 20 pairs (_)
E4,F5: 1.. / E4 = 1  =>  0 pairs (X) / F5 = 1  =>  0 pairs (_)
E4,G4: 1.. / E4 = 1  =>  0 pairs (X) / G4 = 1  =>  0 pairs (_)
E1,E4: 1.. / E1 = 1  =>  0 pairs (*) / E4 = 1  =>  0 pairs (X)
F1,F5: 1.. / F1 = 1  =>  0 pairs (X) / F5 = 1  =>  0 pairs (_)
H5,H9: 1.. / H5 = 1  =>  0 pairs (X) / H9 = 1  => 16 pairs (_)
E3,F3: 5.. / E3 = 5  =>  0 pairs (X) / F3 = 5  =>  0 pairs (_)
E4,F6: 5.. / E4 = 5  =>  0 pairs (*) / F6 = 5  =>  0 pairs (X)
G4,G6: 5.. / G4 = 5  =>  0 pairs (X) / G6 = 5  =>  0 pairs (_)
E4,G4: 5.. / E4 = 5  =>  0 pairs (*) / G4 = 5  =>  0 pairs (X)
F6,G6: 5.. / F6 = 5  =>  0 pairs (X) / G6 = 5  =>  0 pairs (_)
E3,E4: 5.. / E3 = 5  =>  0 pairs (X) / E4 = 5  =>  0 pairs (_)
F3,F6: 5.. / F3 = 5  =>  0 pairs (*) / F6 = 5  =>  0 pairs (X)
C2,C3: 6.. / C2 = 6  =>  0 pairs (X) / C3 = 6  =>  0 pairs (_)
F1,D2: 6.. / F1 = 6  =>  0 pairs (X) / D2 = 6  =>  0 pairs (_)
D6,F6: 6.. / D6 = 6  =>  0 pairs (X) / F6 = 6  =>  0 pairs (_)
G9,I9: 6.. / G9 = 6  => 18 pairs (_) / I9 = 6  =>  0 pairs (X)
F1,I1: 6.. / F1 = 6  =>  0 pairs (X) / I1 = 6  =>  0 pairs (_)
C2,D2: 6.. / C2 = 6  =>  0 pairs (X) / D2 = 6  =>  0 pairs (_)
D2,D6: 6.. / D2 = 6  =>  0 pairs (*) / D6 = 6  =>  0 pairs (X)
F1,F6: 6.. / F1 = 6  =>  0 pairs (X) / F6 = 6  =>  0 pairs (_)
G3,G9: 6.. / G3 = 6  =>  0 pairs (X) / G9 = 6  => 18 pairs (_)
C2,C3: 7.. / C2 = 7  =>  0 pairs (*) / C3 = 7  =>  0 pairs (X)
I5,G6: 7.. / I5 = 7  =>  0 pairs (*) / G6 = 7  =>  0 pairs (X)
E7,F7: 7.. / E7 = 7  =>  0 pairs (*) / F7 = 7  =>  0 pairs (X)
C2,D2: 7.. / C2 = 7  =>  0 pairs (*) / D2 = 7  =>  0 pairs (X)
F5,I5: 7.. / F5 = 7  =>  0 pairs (X) / I5 = 7  =>  0 pairs (_)
D2,D6: 7.. / D2 = 7  =>  0 pairs (X) / D6 = 7  =>  0 pairs (_)
E1,E7: 7.. / E1 = 7  =>  0 pairs (X) / E7 = 7  =>  0 pairs (_)
G3,G6: 7.. / G3 = 7  =>  0 pairs (*) / G6 = 7  =>  0 pairs (X)
E3,F3: 8.. / E3 = 8  =>  0 pairs (*) / F3 = 8  =>  0 pairs (X)
H5,I5: 8.. / H5 = 8  => 16 pairs (_) / I5 = 8  =>  0 pairs (X)
E7,F7: 8.. / E7 = 8  =>  0 pairs (X) / F7 = 8  =>  0 pairs (_)
H9,I9: 8.. / H9 = 8  =>  0 pairs (X) / I9 = 8  => 16 pairs (_)
E3,E7: 8.. / E3 = 8  =>  0 pairs (*) / E7 = 8  =>  0 pairs (X)
F3,F7: 8.. / F3 = 8  =>  0 pairs (X) / F7 = 8  =>  0 pairs (_)
H5,H9: 8.. / H5 = 8  => 16 pairs (_) / H9 = 8  =>  0 pairs (X)
I5,I9: 8.. / I5 = 8  =>  0 pairs (X) / I9 = 8  => 16 pairs (_)
* DURATION: 0:01:13.569464  START: 09:39:18.892712  END: 09:40:32.462176 2017-05-04
* CP COUNT: (39)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (C2,C3,D2,D6,E1,E3,E4,E7,F3,F5,F7,G4,G6,G9,H5,H9,I1)
* 5832..49.41..3982592.4...3.7948.2.6365234.9..831.9..422691..354148563279375924...
* PAIR C3: 6,7 ROW 3
G3: 6,7,1                                # reduction candidate for 6,7
G3: 6,7                                  # 20 pairs
I3: 6,7,1                                # reduction candidate for 6,7
I3: 6,7 => CTR
* 5832..49.41..3982592.4..13.7948125636523479..831695.422691..354148563279375924...
I3: 1                                    # 20 pairs
* PAIR E1: 1,7 BLK 2
F1: 1,7,6                                # reduction candidate for 1,7
F1: 1,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
F1: 6 => CTR
* 5832164974167398259274...3.794852.6365234.9..831.9..422691..354148563279375924...
* PAIR D2: 6,7 BLK 2
F1: 6,7,1                                # reduction candidate for 6,7
F1: 6,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
F1: 1 => CTR
* 5832.149641.6398259264...3.7948125636523479..831.9..422691..354148563279375924...
* PAIR I1: 6,7 BLK 3
G3: 6,7,1                                # reduction candidate for 6,7
G3: 6,7                                  # 20 pairs
I3: 6,7,1                                # reduction candidate for 6,7
I3: 6,7 => CTR
* 5832..49.41..3982592.4..13.7948125636523479..831695.422691..354148563279375924...
I3: 1                                    # 20 pairs
* PAIR I1: 6,7 ROW 1
F1: 6,7,1                                # reduction candidate for 6,7
F1: 6,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
F1: 1 => CTR
* 5832.149641.6398259264...3.7948125636523479..831.9..422691..354148563279375924...
* PAIR F5: 1,7 ROW 5
I5: 1,7,8                                # reduction candidate for 1,7
I5: 8 => CTR
* 5832..49.41..3982592.4...3.7948.2.63652347918831695.422691..354148563279375924...
I5: 1,7                                  # 16 pairs
* PAIR F5: 1,7 COL F
F1: 1,7,6                                # reduction candidate for 1,7
F1: 1,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
F1: 6 => CTR
* 5832164974167398259274...3.794852.6365234.9..831.9..422691..354148563279375924...
* PAIR D6: 6,7 BLK 5
F6: 6,7,5                                # reduction candidate for 6,7
F6: 6,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
F6: 5 => CTR
* 5832.64974167398259274...3.7948.2.6365234.9..831.9..422691..354148563279375924...
* PAIR H5: 1,8 BLK 6
I5: 1,8,7                                # reduction candidate for 1,8
I5: 1,8 => CTR
* 5832..49.41..3982592.4...3.7948.2.636523479..831695.422691..354148563279375924...
I5: 7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
* PAIR G6: 5,7 ROW 6
F6: 5,7,6                                # reduction candidate for 5,7
F6: 5,7 => CTR
* 5832.64974167398259274...3.7948.2.6365234.9..831.9..422691..354148563279375924...
F6: 6 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
* PAIR G9: 1,6 BLK 9
I9: 1,6,8                                # reduction candidate for 1,6
I9: 1,6 => CTR
* 5832..49.41.7398259274...3.7948.25636523479188316957422691..354148563279375924.8.
I9: 8                                    # 16 pairs
* PAIR G9: 1,6 COL G
G3: 1,6,7                                # reduction candidate for 1,6
G3: 1,6 => CTR
* 5832..49.41.7398259274...3.7948.25636523479..8316957422691..354148563279375924...
G3: 7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
* PAIR H9: 1,8 BLK 9
I9: 1,8,6                                # reduction candidate for 1,8
I9: 6 => CTR
* 5832.64974167398259274..6317948.256365234.9.8831.9.7422691..354148563279375924.86
I9: 1,8                                  # 18 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-201-base-pr-000.dot
* REASONING
* DIS # I3: 6,7 => CTR => I3: 1
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* DIS # I3: 6,7 => CTR => I3: 1
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* DIS # I5: 8 => CTR => I5: 1,7
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F6: 6,7 => SOL
* DIS # F6: 5 => CTR => F6: 6,7
* DIS # I5: 1,8 => CTR => I5: 7
* PRF # I5: 7 => SOL
* DIS # F6: 5,7 => CTR => F6: 6
* PRF # F6: 6 => SOL
* DIS # I9: 1,6 => CTR => I9: 8
* DIS # G3: 1,6 => CTR => G3: 7
* PRF # G3: 7 => SOL
* DIS # I9: 6 => CTR => I9: 1,8
* CNT  21 HDP CHAINS /  28 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (C2,C3,D2,D6,E1,E3,E4,E7,F3,F5,F7,G4,G6,G9,H5,H9,I1)
* 5832..49.41..3982592.4...3.7948.2.6365234.9..831.9..422691..354148563279375924...
* PAIR C3: 6,7 ROW 3
G3: 6,7,1                                # reduction candidate for 6,7
G3: 6,7                                  # 20 pairs
I3: 6,7,1                                # reduction candidate for 6,7
I3: 6,7 => CTR
* 5832..49.41..3982592.4..13.7948125636523479..831695.422691..354148563279375924...
* RESTART
* PAIR RESTART
* PAIR E1: 1,7 BLK 2
F1: 1,7,6                                # reduction candidate for 1,7
F1: 1,7 => SOLVED
* 583217496417639825926485731794852163652341987831796542269178354148563279375924618
* DURATION: 0:00:04.268978  START: 09:41:04.838438  END: 09:41:09.107416 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-201-base-pr-001.dot
* REASONING
* DIS # I3: 6,7 => CTR => I3: 1
* PRF I3: 1 # F1: 1,7 => SOL
* STA I3: 1 + F1: 1,7
* CNT   2 HDP CHAINS /   3 HYP OPENED

Header Info

Top 500 Minimum 17 201

solution: 583217496417639825926485731794852163652341987831796542269178354148563279375924618
info: 1890     FNBHWY   S8.f     23347

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

Solution

position: 583217496417639825926485731794852163652341987831796542269178354148563279375924618 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 # G3: 6,7 => UNS
* DIS # I3: 6,7 => CTR => I3: 1
* INC # I3: 1 => UNS
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* INC # G3: 6,7 => UNS
* DIS # I3: 6,7 => CTR => I3: 1
* INC # I3: 1 => UNS
* PRF # F1: 6,7 => SOL
* DIS # F1: 1 => CTR => F1: 6,7
* INC # I5: 1,7 => UNS
* DIS # I5: 8 => CTR => I5: 1,7
* PRF # F1: 1,7 => SOL
* DIS # F1: 6 => CTR => F1: 1,7
* PRF # F6: 6,7 => SOL
* DIS # F6: 5 => CTR => F6: 6,7
* DIS # I5: 1,8 => CTR => I5: 7
* PRF # I5: 7 => SOL
* DIS # F6: 5,7 => CTR => F6: 6
* PRF # F6: 6 => SOL
* DIS # I9: 1,6 => CTR => I9: 8
* INC # I9: 8 => UNS
* DIS # G3: 1,6 => CTR => G3: 7
* PRF # G3: 7 => SOL
* INC # I9: 1,8 => UNS
* DIS # I9: 6 => CTR => I9: 1,8
* CNT  28 HDP CHAINS /  28 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* INC # G3: 6,7 => UNS
* DIS # I3: 6,7 => CTR => I3: 1
* PRF I3: 1 # F1: 1,7 => SOL
* STA I3: 1 + F1: 1,7
* CNT   3 HDP CHAINS /   3 HYP OPENED