Here’s a solution using Set::Scalar:

#! perl
use strict;
use warnings;
use Set::Scalar;

my $range1  = Set::Scalar->new(5 .. 25);
my $range2  = Set::Scalar->new(7 .. 31);
my $common  = $range1->intersection($range2);
my @members = $common->members();

print join(', ', sort { $a <=> $b } @members), "\n";
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Output:

22:25 >perl 764_SoPW.pl
7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 2
+5

22:25 >
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Hope that helps,