Try this. It's a re-casting of the Python algorithm to operate on arrays:
#! perl -slw
use strict;
sub permute3 {
my( $in, $pre ) = ( @_, [] );
return print join '-', @$pre unless @$in;
permute3(
[ @{ $in }[ 0 .. $_-1, $_+1 .. $#$in ] ],
[ @$pre, $in->[ $_ ] ]
) for 0 .. $#$in;
}
permute3( [ qw[ apple banana orange ] ] );;
__END__
C:\test>junk36
apple-banana-orange
apple-orange-banana
banana-apple-orange
banana-orange-apple
orange-apple-banana
orange-banana-apple
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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