Perl

  • http://googlewhacks.blogspot.com/2008/02/perl_24.html
    	use Math::Combinatorics;
    	use utf8;
    	binmode(STDOUT, ":utf8");
    	
    	my @balls = qw(青 赤 黄 緑);
    	
    	print "(1) 4色のボールを順番に並べる\n";
    	print join("\n", map { join " ", @$_ } permute(@balls));
    	print "\n";
    	
    	print "(2) 4色から2色選んで順番に並べる\n";
    	print join("\n", map { join " ", @$_ } (map { permute (@$_) } combine(2, @balls)));
    	print "\n";
    	
    	print "(3) 4色から2色選ぶ組合せ\n";
    	print join("\n", map { join " ", @$_ } combine(2, @balls));
    	print "\n";