Survo puzzles: www.survo.fi/puzzles --------------------------------------- Copyright (c) Survo Systems 2006-2009 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 168/2009 (150) #343-90056 A B C D 1 * * * * 24 2 * * * * 17 3 * * * * 37 20 16 32 10 Survo puzzle 169/2009 (670) #443-94656 A B C D 1 * * 14 * 45 2 * * * * 33 3 * * * * 20 4 * * * * 38 28 54 42 12 Survo puzzle 170/2009 (1350) #443-99072 A B C D 1 * * * * 33 2 * * * * 48 3 * * * * 42 4 * * * * 13 28 49 42 17