Survo puzzles: www.survo.fi/puzzles --------------------------------------- Copyright (c) Survo Systems 2006-2013 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 300/2013 (1000) #443-11022 A B C D 1 * * * * 32 2 * * * * 20 3 * * * * 46 4 * * * * 38 51 13 25 47 Survo puzzle 301/2013 (500) #443-15013 A B C D 1 2 * * * 24 2 * * * * 13 3 * * * * 54 4 * * * * 45 22 39 31 44 Survo puzzle 302/2013 (250) #443-53410 A B C D 1 * * 7 * 20 2 * * * * 16 3 * 10 * * 53 4 * * * * 47 37 23 46 30