Hello Monks, 
my @array=(['john','tom','peter'],['rose','teak'],['car','truck','jeep
+'],['trees','plants'],['good','bad','ugly']);
my @arrayindex=(3,1);
my %hash=();

foreach my $i (@{$array[$arrayindex[0]]}) {
    foreach my $j (@{$array[$arrayindex[1]]}) {
        $hash{"$i $j"}=1;
    }
}

foreach my $i (keys %hash) {
    print "$i=>$hash{$i}\n";
}

The output of the program is a hash whose keys represent all possible 
+combination of values:
trees rose=>1;
trees teak=>1;
plants rose=>1;
plants teak=>1;

[download]
However, I do not know how to handle variable number of elements in @arrayindex, because the above code is rigid and can only work for exactly two elements in @arrayindex (such as @arrayindex=(3,1)). I want the code to be generic so that it can handle any number of elements in @arrayindex, such as, @arrayindex=(3,0,1), @arrayindex=(3,1), @arrayindex=(4,2,1,5), or @arrayindex=(2) etc. Please advise how this can be done. My thinking here was to create the number of foreach loops dynamically, however, don't know if that is even possible. Thank you guys, Raj

In reply to Advice on loops by newbio

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