Analysis of xx-top500-140-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 6.5....2.....71.............1....7.23..6.........4.....7....3..4..8........5...6. initial

Autosolve

position: 6.54..127..4.71.567.1.5643..16..5742347612..525.74.6135721643..46.82.5711..5.7264 autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* PRF # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # B3: 2,9 => SOL
* DIS # B3: 8 => CTR => B3: 2,9
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* PRF # F1: 8,9 => SOL
* DIS # F1: 3 => CTR => F1: 8,9
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* PRF # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* CNT  34 HDP CHAINS /  34 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 # E1: 3,9 => SOL
* STA E1: 3,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

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

Details

Positions

6.5....2.....71.............1....7.23..6.........4.....7....3..4..8........5...6. initial
6.54..127..4.71.567.1.5643..16..5742347612..525.74.6135721643..46.82.5711..5.7264 autosolve
695438127834271956721956438916385742347612895258749613572164389469823571183597264 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (19)
B1: 3,9
A2: 8,9
B2: 2,3
D2: 2,3
D3: 2,9
G2: 8,9
I3: 8,9
A4: 8,9
C6: 8,9
D4: 3,9
F6: 8,9
G5: 8,9
H5: 8,9
C8: 3,9
B9: 8,9
F8: 3,9
E9: 3,9
H7: 8,9
I7: 8,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
B2,B3: 2.. / B2 = 2  =>  0 pairs (X) / B3 = 2  =>  0 pairs (_)
D2,D3: 2.. / D2 = 2  =>  0 pairs (*) / D3 = 2  =>  0 pairs (X)
B2,D2: 2.. / B2 = 2  =>  0 pairs (X) / D2 = 2  =>  0 pairs (_)
B3,D3: 2.. / B3 = 2  =>  0 pairs (*) / D3 = 2  =>  0 pairs (X)
B1,B2: 3.. / B1 = 3  =>  0 pairs (X) / B2 = 3  =>  0 pairs (_)
D4,E4: 3.. / D4 = 3  =>  0 pairs (*) / E4 = 3  =>  0 pairs (X)
C8,C9: 3.. / C8 = 3  =>  0 pairs (X) / C9 = 3  =>  0 pairs (_)
F8,E9: 3.. / F8 = 3  =>  0 pairs (*) / E9 = 3  =>  0 pairs (X)
B2,D2: 3.. / B2 = 3  =>  0 pairs (*) / D2 = 3  =>  0 pairs (X)
C8,F8: 3.. / C8 = 3  =>  0 pairs (X) / F8 = 3  =>  0 pairs (_)
C9,E9: 3.. / C9 = 3  =>  0 pairs (*) / E9 = 3  =>  0 pairs (X)
D2,D4: 3.. / D2 = 3  =>  0 pairs (X) / D4 = 3  =>  0 pairs (_)
F1,F8: 3.. / F1 = 3  =>  0 pairs (X) / F8 = 3  =>  0 pairs (_)
A2,B3: 8.. / A2 = 8  =>  0 pairs (*) / B3 = 8  =>  0 pairs (X)
E1,F1: 8.. / E1 = 8  =>  0 pairs (X) / F1 = 8  =>  0 pairs (_)
G2,I3: 8.. / G2 = 8  =>  0 pairs (X) / I3 = 8  =>  0 pairs (_)
A4,C6: 8.. / A4 = 8  =>  0 pairs (X) / C6 = 8  =>  0 pairs (_)
E4,F6: 8.. / E4 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
G5,H5: 8.. / G5 = 8  =>  0 pairs (*) / H5 = 8  =>  0 pairs (X)
B9,C9: 8.. / B9 = 8  =>  0 pairs (*) / C9 = 8  =>  0 pairs (X)
H7,I7: 8.. / H7 = 8  =>  0 pairs (*) / I7 = 8  =>  0 pairs (X)
A2,G2: 8.. / A2 = 8  =>  0 pairs (*) / G2 = 8  =>  0 pairs (X)
B3,I3: 8.. / B3 = 8  =>  0 pairs (X) / I3 = 8  =>  0 pairs (_)
A4,E4: 8.. / A4 = 8  =>  0 pairs (X) / E4 = 8  =>  0 pairs (_)
C6,F6: 8.. / C6 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
A2,A4: 8.. / A2 = 8  =>  0 pairs (*) / A4 = 8  =>  0 pairs (X)
B3,B9: 8.. / B3 = 8  =>  0 pairs (X) / B9 = 8  =>  0 pairs (_)
C6,C9: 8.. / C6 = 8  =>  0 pairs (*) / C9 = 8  =>  0 pairs (X)
E1,E4: 8.. / E1 = 8  =>  0 pairs (X) / E4 = 8  =>  0 pairs (_)
F1,F6: 8.. / F1 = 8  =>  0 pairs (*) / F6 = 8  =>  0 pairs (X)
G2,G5: 8.. / G2 = 8  =>  0 pairs (X) / G5 = 8  =>  0 pairs (_)
H5,H7: 8.. / H5 = 8  =>  0 pairs (X) / H7 = 8  =>  0 pairs (_)
I3,I7: 8.. / I3 = 8  =>  0 pairs (*) / I7 = 8  =>  0 pairs (X)
G2,I3: 9.. / G2 = 9  =>  0 pairs (*) / I3 = 9  =>  0 pairs (X)
A4,C6: 9.. / A4 = 9  =>  0 pairs (*) / C6 = 9  =>  0 pairs (X)
G5,H5: 9.. / G5 = 9  =>  0 pairs (X) / H5 = 9  =>  0 pairs (_)
F8,E9: 9.. / F8 = 9  =>  0 pairs (X) / E9 = 9  =>  0 pairs (_)
H7,I7: 9.. / H7 = 9  =>  0 pairs (X) / I7 = 9  =>  0 pairs (_)
A2,G2: 9.. / A2 = 9  =>  0 pairs (X) / G2 = 9  =>  0 pairs (_)
C6,F6: 9.. / C6 = 9  =>  0 pairs (X) / F6 = 9  =>  0 pairs (_)
C8,F8: 9.. / C8 = 9  =>  0 pairs (*) / F8 = 9  =>  0 pairs (X)
A2,A4: 9.. / A2 = 9  =>  0 pairs (X) / A4 = 9  =>  0 pairs (_)
D3,D4: 9.. / D3 = 9  =>  0 pairs (*) / D4 = 9  =>  0 pairs (X)
G2,G5: 9.. / G2 = 9  =>  0 pairs (*) / G5 = 9  =>  0 pairs (X)
H5,H7: 9.. / H5 = 9  =>  0 pairs (*) / H7 = 9  =>  0 pairs (X)
I3,I7: 9.. / I3 = 9  =>  0 pairs (X) / I7 = 9  =>  0 pairs (_)
* DURATION: 0:01:18.243282  START: 07:31:35.092812  END: 07:32:53.336094 2017-05-04
* CP COUNT: (46)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A4,B1,B2,B9,C6,C8,D2,D3,D4,E9,F6,F8,G2,G5,H5,H7,I3,I7)
* 6.54..127..4.71.567.1.5643..16..5742347612..525.74.6135721643..46.82.5711..5.7264
* PAIR B1: 3,9 ROW 1
E1: 3,9,8                                # reduction candidate for 3,9
E1: 3,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
E1: 8 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
F1: 3,9,8                                # reduction candidate for 3,9
F1: 3,9 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
F1: 8 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR A2: 8,9 BLK 1
B3: 8,9,2                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 6.54..127.24371.567.125643..16935742347612..52597486135721643..46.82.5711..5.7264
B3: 2 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR D3: 2,9 ROW 3
B3: 2,9,8                                # reduction candidate for 2,9
B3: 2,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
B3: 8 => CTR
* 6.54..127.24371.5678125643981693574234761298525974.6135721643..46.82.5711..5.7264
* PAIR I3: 8,9 ROW 3
B3: 8,9,2                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 6.54..127.24371.567.125643..16935742347612..52597486135721643..46.82.5711..5.7264
B3: 2 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR A4: 8,9 ROW 4
E4: 8,9,3                                # reduction candidate for 8,9
E4: 8,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
E4: 3 => CTR
* 6.548.127..4.71.567.1.5643.816935742347612..525974.6135721643..46.82.5711..5.7264
* PAIR C6: 8,9 COL C
C9: 8,9,3                                # reduction candidate for 8,9
C9: 8,9 => CTR
* 6.54.3127.34271.56721956438.163957423476128952597486135721643894638295711..537264
C9: 3 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR D4: 3,9 BLK 5
E4: 3,9,8                                # reduction candidate for 3,9
E4: 3,9 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
E4: 8 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR F6: 8,9 BLK 5
E4: 8,9,3                                # reduction candidate for 8,9
E4: 8,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
E4: 3 => CTR
* 6.548.127..4.71.567.1.5643.816935742347612..525974.6135721643..46.82.5711..5.7264
* PAIR F6: 8,9 COL F
F1: 8,9,3                                # reduction candidate for 8,9
F1: 8,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
F1: 3 => CTR
* 6.5483127.34271.5672195643881639574234761289525974861357216438946382.5711..5.7264
* PAIR C8: 3,9 BLK 7
C9: 3,9,8                                # reduction candidate for 3,9
C9: 3,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
C9: 8 => CTR
* 635498127..4.71.567.1.5643..16..5742347612..525.74.6135721643..463829571198537264
* PAIR B9: 8,9 BLK 7
C9: 8,9,3                                # reduction candidate for 8,9
C9: 8,9 => CTR
* 6.54.3127.34271.56721956438.163957423476128952597486135721643894638295711..537264
C9: 3 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR B9: 8,9 COL B
B3: 8,9,2                                # reduction candidate for 8,9
B3: 8,9 => CTR
* 6.54..127.24371.567.125643..16935742347612..52597486135721643..46.82.5711..5.7264
B3: 2 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR F8: 3,9 COL F
F1: 3,9,8                                # reduction candidate for 3,9
F1: 3,9 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
F1: 8 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* PAIR E9: 3,9 ROW 9
C9: 3,9,8                                # reduction candidate for 3,9
C9: 3,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
C9: 8 => CTR
* 635498127..4.71.567.1.5643..16..5742347612..525.74.6135721643..463829571198537264
* PAIR E9: 3,9 COL E
E1: 3,9,8                                # reduction candidate for 3,9
E1: 3,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
E1: 8 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
E4: 3,9,8                                # reduction candidate for 3,9
E4: 3,9 => CTR
* 6.548.127..4.71.567.1.5643.816..5742347612..52597486135721643..463829571198537264
E4: 8 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-140-base-pr-000.dot
* REASONING
* PRF # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # B3: 2,9 => SOL
* DIS # B3: 8 => CTR => B3: 2,9
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* PRF # F1: 8,9 => SOL
* DIS # F1: 3 => CTR => F1: 8,9
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* PRF # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* CNT  34 HDP CHAINS /  34 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A4,B1,B2,B9,C6,C8,D2,D3,D4,E9,F6,F8,G2,G5,H5,H7,I3,I7)
* 6.54..127..4.71.567.1.5643..16..5742347612..525.74.6135721643..46.82.5711..5.7264
* PAIR B1: 3,9 ROW 1
E1: 3,9,8                                # reduction candidate for 3,9
E1: 3,9 => SOLVED
* 695438127834271956721956438916385742347612895258749613572164389469823571183597264
* DURATION: 0:00:01.873097  START: 07:33:32.391315  END: 07:33:34.264412 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-140-base-pr-001.dot
* REASONING
* PRF # E1: 3,9 => SOL
* STA E1: 3,9
* CNT   1 HDP CHAINS /   1 HYP OPENED

Header Info

Top 500 Minimum 17 140

solution: 695438127834271956721956438916385742347612895258749613572164389469823571183597264
info: 1813     FNBTWY   S8.f     35525

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

Solution

position: 695438127834271956721956438916385742347612895258749613572164389469823571183597264 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 # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # B3: 2,9 => SOL
* DIS # B3: 8 => CTR => B3: 2,9
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* PRF # E4: 8,9 => SOL
* DIS # E4: 3 => CTR => E4: 8,9
* PRF # F1: 8,9 => SOL
* DIS # F1: 3 => CTR => F1: 8,9
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* DIS # C9: 8,9 => CTR => C9: 3
* PRF # C9: 3 => SOL
* DIS # B3: 8,9 => CTR => B3: 2
* PRF # B3: 2 => SOL
* DIS # F1: 3,9 => CTR => F1: 8
* PRF # F1: 8 => SOL
* PRF # C9: 3,9 => SOL
* DIS # C9: 8 => CTR => C9: 3,9
* PRF # E1: 3,9 => SOL
* DIS # E1: 8 => CTR => E1: 3,9
* DIS # E4: 3,9 => CTR => E4: 8
* PRF # E4: 8 => SOL
* CNT  34 HDP CHAINS /  34 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* PRF # E1: 3,9 => SOL
* STA E1: 3,9
* CNT   1 HDP CHAINS /   1 HYP OPENED