Analysis of xx-top500-064-base.sdk

Contents

Original Sudoku

level: medium

Original Sudoku

position: 16..4.......5..8.2.........2.83..........9.4...5.......4.....6....2..5..7........ initial

Autosolve

position: 162.48.53..45.68.285..324.62.83546.....829.454.56...2854..83267.8.2..534723465.8. autosolve
Autosolve

Pair Reduction Variants

Pair Reduction Analysis

Pair Reduction Analysis

The following important HDP chains were detected:

* DIS # B5: 3,7 => CTR => B5: 1
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # H2: 1,9 => CTR => H2: 7
* PRF # H2: 7 => SOL
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* DIS # B4: 1 => CTR => B4: 7,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # B4: 1,9 => CTR => B4: 7
* PRF # B4: 7 => SOL
* PRF # C8: 1,9 => SOL
* DIS # C8: 6 => CTR => C8: 1,9
* DIS # C8: 6,9 => CTR => C8: 1
* PRF # C8: 1 => SOL
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* CNT  34 HDP CHAINS /  38 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 # B5: 3,7 => CTR => B5: 1
* PRF B5: 1 # D3: 7,9 => SOL
* STA B5: 1 + D3: 7,9
* CNT   2 HDP CHAINS /   2 HYP OPENED

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

Details

Positions

16..4.......5..8.2.........2.83..........9.4...5.......4.....6....2..5..7........ initial
162.48.53..45.68.285..324.62.83546.....829.454.56...2854..83267.8.2..534723465.8. autosolve
162748953934516872857932416278354691316829745495671328549183267681297534723465189 solved

Classification

level: medium

Pairing Analysis

--------------------------------------------------
* PAIRS (20)
A2: 3,9
B2: 3,7
C3: 7,9
D1: 7,9
E2: 1,9
G1: 7,9
A5: 3,6
C5: 6,7
B6: 3,9
E6: 1,7
F6: 1,7
H4: 7,9
I4: 1,9
G6: 3,9
C7: 1,9
A8: 6,9
D7: 1,9
F8: 1,7
G9: 1,9
I9: 1,9

--------------------------------------------------
* CONSTRAINT PAIRS (AUTO SOLVE)
E2,D3: 1.. / E2 = 1  =>  0 pairs (*) / D3 = 1  =>  0 pairs (X)
H2,H3: 1.. / H2 = 1  =>  0 pairs (X) / H3 = 1  =>  0 pairs (_)
B4,B5: 1.. / B4 = 1  =>  0 pairs (X) / B5 = 1  => 19 pairs (_)
E6,F6: 1.. / E6 = 1  =>  0 pairs (X) / F6 = 1  => 18 pairs (_)
I4,G5: 1.. / I4 = 1  => 19 pairs (_) / G5 = 1  =>  0 pairs (X)
C7,C8: 1.. / C7 = 1  =>  0 pairs (X) / C8 = 1  =>  0 pairs (_)
G9,I9: 1.. / G9 = 1  => 19 pairs (_) / I9 = 1  =>  0 pairs (X)
E2,H2: 1.. / E2 = 1  =>  0 pairs (*) / H2 = 1  =>  0 pairs (X)
D3,H3: 1.. / D3 = 1  =>  0 pairs (X) / H3 = 1  =>  0 pairs (_)
B4,I4: 1.. / B4 = 1  =>  0 pairs (X) / I4 = 1  => 19 pairs (_)
B5,G5: 1.. / B5 = 1  => 19 pairs (_) / G5 = 1  =>  0 pairs (X)
C7,D7: 1.. / C7 = 1  =>  0 pairs (X) / D7 = 1  =>  0 pairs (_)
D3,D7: 1.. / D3 = 1  =>  0 pairs (X) / D7 = 1  =>  0 pairs (_)
F6,F8: 1.. / F6 = 1  => 18 pairs (_) / F8 = 1  =>  0 pairs (X)
G5,G9: 1.. / G5 = 1  =>  0 pairs (X) / G9 = 1  => 19 pairs (_)
I4,I9: 1.. / I4 = 1  => 19 pairs (_) / I9 = 1  =>  0 pairs (X)
A2,B2: 3.. / A2 = 3  =>  0 pairs (X) / B2 = 3  =>  0 pairs (_)
G5,G6: 3.. / G5 = 3  =>  0 pairs (X) / G6 = 3  => 20 pairs (_)
B6,G6: 3.. / B6 = 3  =>  0 pairs (X) / G6 = 3  => 20 pairs (_)
A2,A5: 3.. / A2 = 3  =>  0 pairs (X) / A5 = 3  =>  0 pairs (_)
A5,C5: 6.. / A5 = 6  =>  0 pairs (X) / C5 = 6  =>  0 pairs (_)
A8,C8: 6.. / A8 = 6  =>  0 pairs (*) / C8 = 6  =>  0 pairs (X)
A5,A8: 6.. / A5 = 6  =>  0 pairs (X) / A8 = 6  =>  0 pairs (_)
C5,C8: 6.. / C5 = 6  =>  0 pairs (*) / C8 = 6  =>  0 pairs (X)
B2,C3: 7.. / B2 = 7  =>  0 pairs (X) / C3 = 7  =>  0 pairs (_)
D1,D3: 7.. / D1 = 7  =>  0 pairs (*) / D3 = 7  =>  0 pairs (X)
E6,F6: 7.. / E6 = 7  => 18 pairs (_) / F6 = 7  =>  0 pairs (X)
H4,G5: 7.. / H4 = 7  =>  0 pairs (X) / G5 = 7  =>  0 pairs (_)
E8,F8: 7.. / E8 = 7  =>  0 pairs (X) / F8 = 7  => 18 pairs (_)
D1,G1: 7.. / D1 = 7  =>  0 pairs (*) / G1 = 7  =>  0 pairs (X)
B2,H2: 7.. / B2 = 7  =>  0 pairs (X) / H2 = 7  =>  0 pairs (_)
B4,H4: 7.. / B4 = 7  =>  0 pairs (*) / H4 = 7  =>  0 pairs (X)
C3,C5: 7.. / C3 = 7  =>  0 pairs (*) / C5 = 7  =>  0 pairs (X)
E6,E8: 7.. / E6 = 7  => 18 pairs (_) / E8 = 7  =>  0 pairs (X)
F6,F8: 7.. / F6 = 7  =>  0 pairs (X) / F8 = 7  => 18 pairs (_)
G1,G5: 7.. / G1 = 7  =>  0 pairs (X) / G5 = 7  =>  0 pairs (_)
A2,C3: 9.. / A2 = 9  =>  0 pairs (*) / C3 = 9  =>  0 pairs (X)
B4,B6: 9.. / B4 = 9  =>  0 pairs (X) / B6 = 9  => 20 pairs (_)
D7,E8: 9.. / D7 = 9  =>  0 pairs (X) / E8 = 9  =>  0 pairs (_)
G9,I9: 9.. / G9 = 9  =>  0 pairs (X) / I9 = 9  => 19 pairs (_)
D1,G1: 9.. / D1 = 9  =>  0 pairs (X) / G1 = 9  =>  0 pairs (_)
B6,G6: 9.. / B6 = 9  => 20 pairs (_) / G6 = 9  =>  0 pairs (X)
C7,D7: 9.. / C7 = 9  =>  0 pairs (*) / D7 = 9  =>  0 pairs (X)
A2,A8: 9.. / A2 = 9  =>  0 pairs (*) / A8 = 9  =>  0 pairs (X)
E2,E8: 9.. / E2 = 9  =>  0 pairs (X) / E8 = 9  =>  0 pairs (_)
I4,I9: 9.. / I4 = 9  =>  0 pairs (X) / I9 = 9  => 19 pairs (_)
* DURATION: 0:01:59.527237  START: 04:48:29.235561  END: 04:50:28.762798 2017-05-04
* CP COUNT: (46)
* SOLUTION FOUND

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A5,A8,B2,B6,C3,C5,C7,D1,D7,E2,E6,F6,F8,G1,G6,G9,H4,I4,I9)
* 162.48.53..45.68.285..324.62.83546.....829.454.56...2854..83267.8.2..534723465.8.
* PAIR B2: 3,7 COL B
B5: 3,7,1                                # reduction candidate for 3,7
B5: 3,7 => CTR
* 162948753.74516892859732416218354679.37829145495671328541.83267.8.2..534723465981
B5: 1                                    # 19 pairs
* PAIR C3: 7,9 ROW 3
D3: 7,9,1                                # reduction candidate for 7,9
D3: 7,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
D3: 1 => CTR
* 162748953..4596812859132476278354691.168297454956..328541.83267.8.2..534723465.8.
H3: 7,9,1                                # reduction candidate for 7,9
H3: 7,9 => CTR
* 162748953.745968128591324762.83546.....829.454.56...28541983267.8.2..534723465.8.
H3: 1 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR D1: 7,9 BLK 2
D3: 7,9,1                                # reduction candidate for 7,9
D3: 7,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
D3: 1 => CTR
* 162748953..4596812859132476278354691.168297454956..328541.83267.8.2..534723465.8.
* PAIR E2: 1,9 BLK 2
D3: 1,9,7                                # reduction candidate for 1,9
D3: 1,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
D3: 7 => CTR
* 162.48.53..45168.285.7324162.83546....7829.454.5671.2854.183267.8.2..534723465.8.
* PAIR E2: 1,9 ROW 2
H2: 1,9,7                                # reduction candidate for 1,9
H2: 1,9 => CTR
* 162.48.53.745.68.2859.324.62.835467...7829.454.56...28541983267.8.2..534723465.8.
H2: 7 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR E2: 1,9 COL E
E8: 1,9,7                                # reduction candidate for 1,9
E8: 7 => CTR
* 162.48.53..4596812859132476278354691.16829745495617328541.83267.8.2..534723465.8.
E8: 1,9                                  # 18 pairs
* PAIR G1: 7,9 BLK 3
H2: 7,9,1                                # reduction candidate for 7,9
H2: 7,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
H2: 1 => CTR
* 162.48.53.745.68128591324762.83546.....829.454.56...2854..83267.8.2..534723465.8.
H3: 7,9,1                                # reduction candidate for 7,9
H3: 7,9 => CTR
* 162748953.745968128591324762.83546.....829.454.56...28541983267.8.2..534723465.8.
H3: 1 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR E6: 1,7 COL E
E8: 1,7,9                                # reduction candidate for 1,7
E8: 1,7 => CTR
* 162.48.53..4596812859132476278354691.168297454956..328541.83267.8.2..534723465.8.
E8: 9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR H4: 7,9 ROW 4
B4: 7,9,1                                # reduction candidate for 7,9
B4: 1 => CTR
* 162948753.74516892859732416218354679.37829145495671328541.83267.8.2..534723465981
B4: 7,9                                  # 19 pairs
* PAIR H4: 7,9 COL H
H2: 7,9,1                                # reduction candidate for 7,9
H2: 7,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
H2: 1 => CTR
* 162.48.53.745.68128591324762.83546.....829.454.56...2854..83267.8.2..534723465.8.
H3: 7,9,1                                # reduction candidate for 7,9
H3: 7,9 => CTR
* 162748953.745968128591324762.83546.....829.454.56...28541983267.8.2..534723465.8.
H3: 1 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR I4: 1,9 ROW 4
B4: 1,9,7                                # reduction candidate for 1,9
B4: 1,9 => CTR
* 162.48753.745.68.28597324162.835467...7829.454.56...28541.83267.8.2..534723465.8.
B4: 7 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR C7: 1,9 BLK 7
C8: 1,9,6                                # reduction candidate for 1,9
C8: 1,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
C8: 6 => CTR
* 16274895337459681285..324.62.83546.....829.454.56...285419832679862..534723465.8.
* PAIR A8: 6,9 BLK 7
C8: 6,9,1                                # reduction candidate for 6,9
C8: 6,9 => CTR
* 162748953..4596812859132476278354691.16829.454.56...28541983267.8.2..534723465.8.
C8: 1 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* PAIR D7: 1,9 BLK 8
E8: 1,9,7                                # reduction candidate for 1,9
E8: 7 => CTR
* 162.48.53..4596812859132476278354691.16829745495617328541.83267.8.2..534723465.8.
E8: 1,9                                  # 18 pairs
* PAIR D7: 1,9 COL D
D3: 1,9,7                                # reduction candidate for 1,9
D3: 1,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
D3: 7 => CTR
* 162.48.53..45168.285.7324162.83546....7829.454.5671.2854.183267.8.2..534723465.8.
* PAIR F8: 1,7 BLK 8
E8: 1,7,9                                # reduction candidate for 1,7
E8: 1,7 => CTR
* 162.48.53..4596812859132476278354691.168297454956..328541.83267.8.2..534723465.8.
E8: 9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* INCONCLUSIVE
* SAVE PR GRAPH xx-top500-064-base-pr-000.dot
* REASONING
* DIS # B5: 3,7 => CTR => B5: 1
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # H2: 1,9 => CTR => H2: 7
* PRF # H2: 7 => SOL
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* DIS # B4: 1 => CTR => B4: 7,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # B4: 1,9 => CTR => B4: 7
* PRF # B4: 7 => SOL
* PRF # C8: 1,9 => SOL
* DIS # C8: 6 => CTR => C8: 1,9
* DIS # C8: 6,9 => CTR => C8: 1
* PRF # C8: 1 => SOL
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* CNT  34 HDP CHAINS /  38 HYP OPENED

--------------------------------------------------
* PREPARE PR GRAPH
* PAIR REDUCTION ..
* LEVEL 0 PASS 1 ROUND 1 (AUTO SOLVE) (A2,A5,A8,B2,B6,C3,C5,C7,D1,D7,E2,E6,F6,F8,G1,G6,G9,H4,I4,I9)
* 162.48.53..45.68.285..324.62.83546.....829.454.56...2854..83267.8.2..534723465.8.
* PAIR B2: 3,7 COL B
B5: 3,7,1                                # reduction candidate for 3,7
B5: 3,7 => CTR
* 162948753.74516892859732416218354679.37829145495671328541.83267.8.2..534723465981
* PAIR RESTART
* PAIR C3: 7,9 ROW 3
D3: 7,9,1                                # reduction candidate for 7,9
D3: 7,9 => SOLVED
* 162748953934516872857932416278354691316829745495671328549183267681297534723465189
* DURATION: 0:00:06.274717  START: 04:51:28.638002  END: 04:51:34.912719 2017-05-04
* SOLUTION FOUND
* SAVE PR GRAPH xx-top500-064-base-pr-001.dot
* REASONING
* DIS # B5: 3,7 => CTR => B5: 1
* PRF B5: 1 # D3: 7,9 => SOL
* STA B5: 1 + D3: 7,9
* CNT   2 HDP CHAINS /   2 HYP OPENED

Header Info

Top 500 Minimum 17 064

solution: 162748953934516872857932416278354691316829745495671328549183267681297534723465189
info: 1440     FNBHWY   S8.f     26529

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

Solution

position: 162748953934516872857932416278354691316829745495671328549183267681297534723465189 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:

* DIS # B5: 3,7 => CTR => B5: 1
* INC # B5: 1 => UNS
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* PRF # D3: 7,9 => SOL
* DIS # D3: 1 => CTR => D3: 7,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # H2: 1,9 => CTR => H2: 7
* PRF # H2: 7 => SOL
* INC # E8: 1,9 => UNS
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* INC # B4: 7,9 => UNS
* DIS # B4: 1 => CTR => B4: 7,9
* PRF # H2: 7,9 => SOL
* DIS # H2: 1 => CTR => H2: 7,9
* DIS # H3: 7,9 => CTR => H3: 1
* PRF # H3: 1 => SOL
* DIS # B4: 1,9 => CTR => B4: 7
* PRF # B4: 7 => SOL
* PRF # C8: 1,9 => SOL
* DIS # C8: 6 => CTR => C8: 1,9
* DIS # C8: 6,9 => CTR => C8: 1
* PRF # C8: 1 => SOL
* INC # E8: 1,9 => UNS
* DIS # E8: 7 => CTR => E8: 1,9
* PRF # D3: 1,9 => SOL
* DIS # D3: 7 => CTR => D3: 1,9
* DIS # E8: 1,7 => CTR => E8: 9
* PRF # E8: 9 => SOL
* CNT  38 HDP CHAINS /  38 HYP OPENED

A2. Pair Reduction

Full list of HDP chains traversed:

* DIS # B5: 3,7 => CTR => B5: 1
* PRF B5: 1 # D3: 7,9 => SOL
* STA B5: 1 + D3: 7,9
* CNT   2 HDP CHAINS /   2 HYP OPENED