Analysis of xx-top500-073-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 4....6.5.......3.9...8........12.8..5..7.....6............5..4..8...3....1....... initial

Autosolve

position: 4....61588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # C1: 7,9 => SOL
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* DIS # B7: 6 => CTR => B7: 7,9
* DIS # C2: 6,7 => CTR => C2: 2
* PRF # C2: 2 => SOL
* PRF # B7: 6,7 => SOL
* DIS # B7: 9 => CTR => B7: 6,7
* DIS # C1: 3,9 => CTR => C1: 2,7
* PRF # C1: 2,7 => SOL
* DIS # C1: 2,9 => CTR => C1: 3,7
* PRF # C1: 3,7 => SOL
* PRF # E1: 3,9 => SOL
* DIS # E1: 7 => CTR => E1: 3,9
* PRF # H3: 2,7 => SOL
* PRF # H3: 2,7 => SOL
* DIS # C2: 6 => CTR => C2: 2,7
* DIS # A8: 7,9 => CTR => A8: 2
* PRF # A8: 2 => SOL
* PRF # C1: 7,9 => SOL
* DIS # C7: 7,9 => CTR => C7: 6
* DIS # G5: 2 => CTR => G5: 4,9
* DIS # G6: 4,9 => CTR => G6: 5,7
* DIS # G5: 9 => CTR => G5: 2,4
* DIS # I3: 7 => CTR => I3: 2,4
* DIS # H8: 7,9 => CTR => H8: 2,6
* PRF # A8: 2,9 => SOL
* DIS # A8: 7 => CTR => A8: 2,9
* PRF # G7: 2,9 => SOL
* DIS # G7: 7 => CTR => G7: 2,9
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* CNT  32 HDP CHAINS /  54 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 # C1: 7,9 => SOL
* STA C1: 7,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

4....6.5.......3.9...8........12.8..5..7.....6............5..4..8...3....1....... initial
4....61588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83 autosolve
497236158862541379153897624749125836538769412621384795376958241285413967914672583 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (22)
B1: 7,9
B2: 6,7
C3: 3,9
D1: 2,9
E3: 3,9
F3: 2,7
H2: 2,7
A4: 7,9
C4: 7,9
F5: 4,9
F6: 4,9
I5: 2,4
H6: 7,9
C8: 4,5
A9: 2,9
C9: 4,5
D7: 2,9
D8: 4,6
D9: 4,6
E9: 7,9
F9: 2,7
G9: 5,6

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
C1,C2: 2.. / C1 = 2  =>  0 pairs (X) / C2 = 2  =>  0 pairs (_)
D1,F3: 2.. / D1 = 2  =>  0 pairs (*) / F3 = 2  =>  0 pairs (X)
G5,I5: 2.. / G5 = 2  =>  0 pairs (X) / I5 = 2  => 24 pairs (_)
A8,A9: 2.. / A8 = 2  =>  0 pairs (*) / A9 = 2  =>  0 pairs (X)
D7,F9: 2.. / D7 = 2  =>  0 pairs (X) / F9 = 2  =>  0 pairs (_)
C1,D1: 2.. / C1 = 2  =>  0 pairs (X) / D1 = 2  =>  0 pairs (_)
C2,H2: 2.. / C2 = 2  =>  0 pairs (*) / H2 = 2  =>  0 pairs (X)
D7,G7: 2.. / D7 = 2  =>  0 pairs (X) / G7 = 2  =>  0 pairs (_)
A9,F9: 2.. / A9 = 2  =>  0 pairs (X) / F9 = 2  =>  0 pairs (_)
D1,D7: 2.. / D1 = 2  =>  0 pairs (*) / D7 = 2  =>  0 pairs (X)
F3,F9: 2.. / F3 = 2  =>  0 pairs (X) / F9 = 2  =>  0 pairs (_)
C1,C3: 3.. / C1 = 3  =>  0 pairs (X) / C3 = 3  =>  0 pairs (_)
E1,E3: 3.. / E1 = 3  =>  0 pairs (*) / E3 = 3  =>  0 pairs (X)
C1,E1: 3.. / C1 = 3  =>  0 pairs (X) / E1 = 3  =>  0 pairs (_)
C3,E3: 3.. / C3 = 3  =>  0 pairs (*) / E3 = 3  =>  0 pairs (X)
G3,I3: 4.. / G3 = 4  => 24 pairs (_) / I3 = 4  => 24 pairs (_)
F5,F6: 4.. / F5 = 4  =>  0 pairs (X) / F6 = 4  => 22 pairs (_)
C8,C9: 4.. / C8 = 4  => 17 pairs (_) / C9 = 4  => 18 pairs (_)
D8,D9: 4.. / D8 = 4  => 18 pairs (_) / D9 = 4  => 17 pairs (_)
C8,D8: 4.. / C8 = 4  => 17 pairs (_) / D8 = 4  => 18 pairs (_)
C9,D9: 4.. / C9 = 4  => 18 pairs (_) / D9 = 4  => 17 pairs (_)
G6,I6: 5.. / G6 = 5  => 18 pairs (_) / I6 = 5  => 23 pairs (_)
C8,C9: 5.. / C8 = 5  => 18 pairs (_) / C9 = 5  => 17 pairs (_)
C9,G9: 5.. / C9 = 5  => 17 pairs (_) / G9 = 5  => 18 pairs (_)
I6,I8: 5.. / I6 = 5  => 23 pairs (_) / I8 = 5  => 18 pairs (_)
B2,C2: 6.. / B2 = 6  => 23 pairs (_) / C2 = 6  =>  0 pairs (X)
G3,H3: 6.. / G3 = 6  =>  0 pairs (*) / H3 = 6  =>  0 pairs (X)
B7,C7: 6.. / B7 = 6  =>  0 pairs (X) / C7 = 6  => 23 pairs (_)
D8,D9: 6.. / D8 = 6  => 17 pairs (_) / D9 = 6  => 18 pairs (_)
D9,G9: 6.. / D9 = 6  => 18 pairs (_) / G9 = 6  => 17 pairs (_)
B2,B7: 6.. / B2 = 6  => 23 pairs (_) / B7 = 6  =>  0 pairs (X)
C2,C7: 6.. / C2 = 6  =>  0 pairs (X) / C7 = 6  => 23 pairs (_)
H3,H8: 6.. / H3 = 6  => 22 pairs (_) / H8 = 6  =>  0 pairs (*)
E1,F3: 7.. / E1 = 7  =>  0 pairs (X) / F3 = 7  =>  0 pairs (_)
A4,C4: 7.. / A4 = 7  =>  0 pairs (*) / C4 = 7  =>  0 pairs (X)
E9,F9: 7.. / E9 = 7  =>  0 pairs (*) / F9 = 7  =>  0 pairs (X)
A4,A8: 7.. / A4 = 7  =>  0 pairs (*) / A8 = 7  =>  0 pairs (X)
E1,E9: 7.. / E1 = 7  =>  0 pairs (X) / E9 = 7  =>  0 pairs (_)
F3,F9: 7.. / F3 = 7  =>  0 pairs (*) / F9 = 7  =>  0 pairs (X)
A4,C4: 9.. / A4 = 9  =>  0 pairs (X) / C4 = 9  =>  0 pairs (_)
F5,F6: 9.. / F5 = 9  => 22 pairs (_) / F6 = 9  =>  0 pairs (X)
D7,E9: 9.. / D7 = 9  =>  0 pairs (*) / E9 = 9  =>  0 pairs (X)
C3,E3: 9.. / C3 = 9  =>  0 pairs (X) / E3 = 9  =>  0 pairs (_)
F5,G5: 9.. / F5 = 9  => 22 pairs (_) / G5 = 9  =>  0 pairs (X)
A9,E9: 9.. / A9 = 9  =>  0 pairs (*) / E9 = 9  =>  0 pairs (X)
B1,B7: 9.. / B1 = 9  =>  0 pairs (*) / B7 = 9  =>  0 pairs (X)
D1,D7: 9.. / D1 = 9  =>  0 pairs (X) / D7 = 9  =>  0 pairs (_)
H6,H8: 9.. / H6 = 9  => 22 pairs (_) / H8 = 9  =>  0 pairs (X)
* DURATION: 0:01:33.288810  START: 05:11:42.136671  END: 05:13:15.425481 2017-05-04
* CP COUNT: (48)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A9,B1,B2,C3,C4,C8,C9,D1,D7,D8,D9,E3,E9,F3,F5,F6,F9,G9,H2,H6,I5)
* 4....61588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
* PAIR B1: 7,9 BLK 1
C1: 7,9,2,3                              # reduction candidate for 7,9
C1: 7,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
C1: 2,3                                  # 23 pairs
* PAIR B1: 7,9 ROW 1
E1: 7,9,3                                # reduction candidate for 7,9
E1: 7,9 => CTR
* 4.32.61588.2541379159837...94712583653876..1.62138..9.39..58.41.8..13....1.....83
E1: 3 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR B1: 7,9 COL B
B7: 7,9,6                                # reduction candidate for 7,9
B7: 6 => CTR
* 49.2.615887.5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
B7: 7,9                                  # 23 pairs
* PAIR B2: 6,7 BLK 1
C2: 6,7,2                                # reduction candidate for 6,7
C2: 6,7 => CTR
* 4.29361588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
C2: 2 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR B2: 6,7 COL B
B7: 6,7,9                                # reduction candidate for 6,7
B7: 6,7 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
B7: 9 => CTR
* 472..615886.5413.915.8......4.12583653876..1.62138....39625874178..13...21..97.83
* PAIR C3: 3,9 BLK 1
C1: 3,9,2,7                              # reduction candidate for 3,9
C1: 3,9 => CTR
* 4..2.61588.254137915.8.7....4.12583653876..1.62138..9.3.695824128..1396791.672583
C1: 2,7 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR D1: 2,9 ROW 1
C1: 2,9,3,7                              # reduction candidate for 2,9
C1: 2,9 => CTR
* 4...361588..5413.9153897....4.12583653876..1.62138....3..95824128..13...91..72.83
C1: 3,7 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR E3: 3,9 BLK 2
E1: 3,9,7                                # reduction candidate for 3,9
E1: 3,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
E1: 7 => CTR
* 4.32761588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
* PAIR F3: 2,7 ROW 3
G3: 2,7,4,6                              # reduction candidate for 2,7
G3: 2,7                                  # 25 pairs
H3: 2,7,6                                # reduction candidate for 2,7
H3: 2,7 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
H3: 6                                    # 22 pairs
I3: 2,7,4                                # reduction candidate for 2,7
I3: 2,7                                  # 24 pairs
* PAIR H2: 2,7 BLK 3
G3: 2,7,4,6                              # reduction candidate for 2,7
G3: 2,7                                  # 25 pairs
H3: 2,7,6                                # reduction candidate for 2,7
H3: 2,7 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
H3: 6                                    # 22 pairs
I3: 2,7,4                                # reduction candidate for 2,7
I3: 2,7                                  # 24 pairs
* PAIR H2: 2,7 ROW 2
C2: 2,7,6                                # reduction candidate for 2,7
C2: 6 => CTR
* 4.29361588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
C2: 2,7                                  # 23 pairs
* PAIR H2: 2,7 COL H
H8: 2,7,6,9                              # reduction candidate for 2,7
H8: 6,9                                  # 24 pairs
H8: 2,7                                  # 23 pairs
* PAIR A4: 7,9 COL A
A8: 7,9,2                                # reduction candidate for 7,9
A8: 7,9 => CTR
* 4..9761588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13...21..97.83
A8: 2 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR C4: 7,9 COL C
C1: 7,9,2,3                              # reduction candidate for 7,9
C1: 7,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
C1: 2,3                                  # 23 pairs
C7: 7,9,6                                # reduction candidate for 7,9
C7: 7,9 => CTR
* 49...61588.654132915.8.2....4.12583653876..1.62138....36.258.41.8..13...21..97.83
C7: 6                                    # 23 pairs
* PAIR F5: 4,9 ROW 5
G5: 4,9,2                                # reduction candidate for 4,9
G5: 2 => CTR
* 4.29.61588..5413.915.8......4.125836538769214621384...3..258.41.8..13...21..97.83
G5: 4,9                                  # 24 pairs
* PAIR F6: 4,9 ROW 6
G6: 4,9,5,7                              # reduction candidate for 4,9
G6: 4,9 => CTR
* 4.29.61588..54132915.8.2.6..4.12583653876..1.62138..753..25874178..13.9221..97.83
G6: 5,7                                  # 23 pairs
* PAIR I5: 2,4 BLK 6
G5: 2,4,9                                # reduction candidate for 2,4
G5: 9 => CTR
* 4.29.61588..54132915.8.2.6..4.125836538764912621389.7.3..25874178..13295215497683
G5: 2,4                                  # 22 pairs
* PAIR I5: 2,4 COL I
I3: 2,4,7                                # reduction candidate for 2,4
I3: 7 => CTR
* 4...761588..54132915.832467.4.12583653876..1.62138....3..258.41.8..13...21..97.83
I3: 2,4                                  # 25 pairs
* PAIR H6: 7,9 BLK 6
G6: 7,9,4,5                              # reduction candidate for 7,9
G6: 7,9                                  # 23 pairs
G6: 4,5                                  # 23 pairs
* PAIR H6: 7,9 COL H
H8: 7,9,2,6                              # reduction candidate for 7,9
H8: 7,9 => CTR
* 4.29.61588..54132915.8.2.6..4.12583653876..1.62138....3..258.41.8..13...21..97.83
H8: 2,6                                  # 25 pairs
* PAIR A9: 2,9 BLK 7
A8: 2,9,7                                # reduction candidate for 2,9
A8: 2,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
A8: 7 => CTR
* 4..9761588..5413.915.8......4.12583653876..1.62138....3...58.4178..13...21..97.83
* PAIR D7: 2,9 ROW 7
G7: 2,9,7                                # reduction candidate for 2,9
G7: 2,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
G7: 7 => CTR
* 4.29.61588..5413.915.8......4.12583653876..1.62138....3..25874178..13...21..97.83
* PAIR E9: 7,9 COL E
E1: 7,9,3                                # reduction candidate for 7,9
E1: 7,9 => CTR
* 4.32.61588.2541379159837...94712583653876..1.62138..9.39..58.41.8..13....1.....83
E1: 3 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* PAIR G9: 5,6 BLK 9
G8: 5,6,2,7,9                            # reduction candidate for 5,6
G8: 5,6                                  # 24 pairs
G8: 2,7,9                                # 22 pairs
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-073-base-pr-000.dot
* REASONING
* PRF # C1: 7,9 => SOL
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* DIS # B7: 6 => CTR => B7: 7,9
* DIS # C2: 6,7 => CTR => C2: 2
* PRF # C2: 2 => SOL
* PRF # B7: 6,7 => SOL
* DIS # B7: 9 => CTR => B7: 6,7
* DIS # C1: 3,9 => CTR => C1: 2,7
* PRF # C1: 2,7 => SOL
* DIS # C1: 2,9 => CTR => C1: 3,7
* PRF # C1: 3,7 => SOL
* PRF # E1: 3,9 => SOL
* DIS # E1: 7 => CTR => E1: 3,9
* PRF # H3: 2,7 => SOL
* PRF # H3: 2,7 => SOL
* DIS # C2: 6 => CTR => C2: 2,7
* DIS # A8: 7,9 => CTR => A8: 2
* PRF # A8: 2 => SOL
* PRF # C1: 7,9 => SOL
* DIS # C7: 7,9 => CTR => C7: 6
* DIS # G5: 2 => CTR => G5: 4,9
* DIS # G6: 4,9 => CTR => G6: 5,7
* DIS # G5: 9 => CTR => G5: 2,4
* DIS # I3: 7 => CTR => I3: 2,4
* DIS # H8: 7,9 => CTR => H8: 2,6
* PRF # A8: 2,9 => SOL
* DIS # A8: 7 => CTR => A8: 2,9
* PRF # G7: 2,9 => SOL
* DIS # G7: 7 => CTR => G7: 2,9
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* CNT  32 HDP CHAINS /  54 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A4,A9,B1,B2,C3,C4,C8,C9,D1,D7,D8,D9,E3,E9,F3,F5,F6,F9,G9,H2,H6,I5)
* 4....61588..5413.915.8......4.12583653876..1.62138....3...58.41.8..13....1.....83
* PAIR B1: 7,9 BLK 1
C1: 7,9,2,3                              # reduction candidate for 7,9
C1: 7,9 => SOLVED
* 497236158862541379153897624749125836538769412621384795376958241285413967914672583
* DURATION: 0:00:02.433765  START: 05:14:17.780094  END: 05:14:20.213859 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-073-base-pr-001.dot
* REASONING
* PRF # C1: 7,9 => SOL
* STA C1: 7,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 073

solution: 497236158862541379153897624749125836538769412621384795376958241285413967914672583
info: 1473     FNBTHWXY S8.f     30577

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

Solution

position: 497236158862541379153897624749125836538769412621384795376958241285413967914672583 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 # C1: 7,9 => SOL
* INC # C1: 2,3 => UNS
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* INC # B7: 7,9 => UNS
* DIS # B7: 6 => CTR => B7: 7,9
* DIS # C2: 6,7 => CTR => C2: 2
* PRF # C2: 2 => SOL
* PRF # B7: 6,7 => SOL
* DIS # B7: 9 => CTR => B7: 6,7
* DIS # C1: 3,9 => CTR => C1: 2,7
* PRF # C1: 2,7 => SOL
* DIS # C1: 2,9 => CTR => C1: 3,7
* PRF # C1: 3,7 => SOL
* PRF # E1: 3,9 => SOL
* DIS # E1: 7 => CTR => E1: 3,9
* INC # G3: 2,7 => UNS
* PRF # H3: 2,7 => SOL
* INC # H3: 6 => UNS
* INC # I3: 2,7 => UNS
* INC # G3: 2,7 => UNS
* PRF # H3: 2,7 => SOL
* INC # H3: 6 => UNS
* INC # I3: 2,7 => UNS
* INC # C2: 2,7 => UNS
* DIS # C2: 6 => CTR => C2: 2,7
* INC # H8: 2,7 => UNS
* INC # H8: 6,9 => UNS
* DIS # A8: 7,9 => CTR => A8: 2
* PRF # A8: 2 => SOL
* PRF # C1: 7,9 => SOL
* INC # C1: 2,3 => UNS
* DIS # C7: 7,9 => CTR => C7: 6
* INC # C7: 6 => UNS
* INC # G5: 4,9 => UNS
* DIS # G5: 2 => CTR => G5: 4,9
* DIS # G6: 4,9 => CTR => G6: 5,7
* INC # G6: 5,7 => UNS
* INC # G5: 2,4 => UNS
* DIS # G5: 9 => CTR => G5: 2,4
* INC # I3: 2,4 => UNS
* DIS # I3: 7 => CTR => I3: 2,4
* INC # G6: 7,9 => UNS
* INC # G6: 4,5 => UNS
* DIS # H8: 7,9 => CTR => H8: 2,6
* INC # H8: 2,6 => UNS
* PRF # A8: 2,9 => SOL
* DIS # A8: 7 => CTR => A8: 2,9
* PRF # G7: 2,9 => SOL
* DIS # G7: 7 => CTR => G7: 2,9
* DIS # E1: 7,9 => CTR => E1: 3
* PRF # E1: 3 => SOL
* INC # G8: 5,6 => UNS
* INC # G8: 2,7,9 => UNS
* CNT  54 HDP CHAINS /  54 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # C1: 7,9 => SOL
* STA C1: 7,9
* CNT   1 HDP CHAINS /   1 HYP OPENED