... by: Serban
% 545
1. Column 3 n=4 e=5 Nc=14 Ns=13 => B3=2 & C3=1 solve
2. Box 1 ABC123 n=2 e=7 Nc=34 Ns=22 => A1=4 & C2=9 solve
3. Box 5 DEF456 n=3 e=6 Nc=22 Ns=8 => D4=5 & E5=6 basics to 67
3a. BUG+1 => F3=4 solve
3b. X-chain x=4 => [F1,BD3,F8,A9] <>4 => A1=4 solve
... by: Valery
File "#545".
Total solving time is: 6 sec.
The number of cycles: 49.
Trial and error.
Number of selected cells 4:
A2=8 A5=2 G7=4 G9=8
007 300 090..........487 325 196
600 001 000..........632 891 547
000 040 800..........591 746 823
900 007 000..........926 517 384
003 200 000..........873 264 915
050 080 000..........154 983 762
205 009 070..........265 139 478
040 050 001..........749 658 231
008 000 600..........318 472 659
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