Solve W137 Task 2.

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diff --git a/challenge-137/bob-lied/perl/ch-2.pl b/challenge-137/bob-lied/perl/ch-2.pl
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+#!/usr/bin/env perl
+# vim:set ts=4 sw=4 sts=4 et ai wm=0 nu:
+#=============================================================================
+# ch-2.pl
+#=============================================================================
+# Copyright (c) 2021, Bob Lied
+#=============================================================================
+# Perl Weekly Challenge week 137, Task #2, Lychrel number 
+#
+# You are given a number, 10 <= $n <= 1000.
+# Write a script to find out if the given number is Lychrel number. To keep
+# the task simple, we impose the following rules:
+#   a. Stop if the number of iterations reached 500.
+#   b. Stop if you end up with number >= 10_000_000.
+#
+# According to wikipedia:
+# A Lychrel number is a natural number that cannot form a palindrome through
+# the iterative process of repeatedly reversing its digits and adding the
+# resulting numbers.
+#
+# Example 1: Input $n = 56, Output = 0
+#   56+65 = 121, found palindrome after 1 iteration
+#
+# Example 2: Input $n = 57, Output = 0
+#   57+75 = 132
+#   132+231 = 363, found palindrome after 2 iterations
+#=============================================================================
+
+use strict;
+use warnings;
+use v5.32;
+
+use experimental qw/ signatures /;
+no warnings "experimental::signatures";
+
+use Getopt::Long;
+my $Verbose = 0;
+my $DoTest  = 0;
+
+my $MaxIter = 500;
+my $MaxSum  = 10_000_000;
+
+GetOptions("test" => \$DoTest, "verbose" => \$Verbose);
+exit(!runTest()) if $DoTest;
+
+sub isPalindrome($n)
+{
+    return 1 if $n < 10;
+    my @dig = split("", $n);
+    while ( @dig && $dig[0] == $dig[-1] )
+    {
+        @dig = @dig[ 1 .. $#dig-1 ];
+    }
+    return @dig == 0;
+}
+
+sub isLychrel($n)
+{
+    my $iter = 0;
+    my $sum  = $n;
+    while ( $iter < $MaxIter && $sum < $MaxSum )
+    {
+        my $revn = join("", reverse split(//, $n));
+        $sum = $n + $revn;
+        say "$iter: $n + $revn = $sum" if $Verbose;
+        return 0 if isPalindrome($sum);
+        $n = $sum;
+    }
+    return 1;
+}
+
+sub runTest
+{
+    use Test::More;
+
+    is( isPalindrome(   1),  1, "P=1");
+    is( isPalindrome(  22),  1, "P=22");
+    is( isPalindrome(  27), '', "P=27");
+    is( isPalindrome( 343),  1, "P=343");
+    is( isPalindrome( 346), '', "P=346");
+
+    is( isLychrel( 56), 0, "N=56");
+    is( isLychrel( 57), 0, "N=57");
+    is( isLychrel( 59), 0, "N=59");
+    is( isLychrel(196), 1, "N=196");
+
+    done_testing;
+}
+