Perl solution for week 137. part 2

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diff --git a/challenge-137/abigail/perl/ch-2.pl b/challenge-137/abigail/perl/ch-2.pl
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+++ b/challenge-137/abigail/perl/ch-2.pl
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+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See ../README.md
+#
+
+#
+# Run as: perl ch-2.pl < input-file
+#
+
+#
+# Note that the challenge says we can terminate the process of iterating
+# if we have had 500 iterations. We will never hit that: for all numbers
+# between 10 and 1000, we either reach a palindrome or exceed 10_000_000
+# long before hitting the 500th iteration (11 iterations is the maximum
+# amount of iterations we need). So, we just won't bother tracking the
+# number of iterations.
+#
+
+sub l ($n) {$n >= 10_000_000 ? 1 : $n eq reverse ($n) ? 0 : l ($n + reverse $n)}
+say l s/\n//r while <>;