Hi Lanx, I have two questions:-

1. Could you please explain me this part of the code posted by anonymous 

for my $triplet ( @S ){
        my %Pie;
        undef @Pie{@$QT};
        delete @Pie{ @$triplet };
        print "@$triplet\n" if keys(%Pie) <= ( @$QT - @$triplet ) ;

[download]

2. If I call this code as a subroutine,how do I save the retun value of this subroutine. 

sub induced {
my (@z)=@_;
for my $QT (\@z ){
    #print Dumper $QT;
    for my $triplet ( @trip ){
        my %Pie;
        undef @Pie{@$QT};
        delete @Pie{ @$triplet };
        print "@$triplet\n" if keys(%Pie) <= ( @$QT - @$triplet ) ;
        return @$triplet;
    }
}}
my @C;
my $d;
my $p=$#subgraphs+1;
for ($d=$p; $d >=1; $d--)
  { 
    print "component $d = @{ $subgraphs[$d-1] }\n";
    my ($qw,$we,$er)=&induced(@{ $subgraphs[$d-1] });
     

}
----------OUTPUT------------
component 2 = e d
component 1 = c a b
b c a

[download]

But I want to save the return value "b c a"

In reply to Re^2: Finding subgraphs induced by a set of given vertices. by zing
in thread Finding subgraphs induced by a set of given vertices. by zing

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