Survo puzzles: www.survo.fi/puzzles
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Copyright (c) Survo Systems 2006-2011

The easiest way to solve these three problems may be
using a Java Applet
http://www.survo.fi/swap/puzzles.html
based on the swapping method.

Survo puzzle 237/2011 (240) #443-86034

   A  B  C  D
1 11  *  *  * 54
2  *  *  *  * 11
3  *  *  *  * 28
4  *  *  *  * 43
  23 46 37 30

Survo puzzle 238/2011 (580) #443-97080

   A  B  C  D
1  *  *  *  * 38
2 13  *  *  * 28
3  *  *  *  * 19
4  *  *  *  * 51
  56 34 26 20

Survo puzzle 239/2011 (10000) #453-14994

   A  B  C  D  E
1  *  *  *  *  * 38
2  *  *  *  *  * 63
3  *  *  *  *  * 83
4  *  *  *  *  * 26
  42 51 63 21 33