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diff --git a/challenge-288/wanderdoc/perl/ch-1.pl b/challenge-288/wanderdoc/perl/ch-1.pl
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+#!perl
+use strict;
+use warnings FATAL => qw(all);
+
+=prompt
+You are given a string, $str, which is an integer.
+
+Write a script to find out the closest palindrome, not including itself. If there are more than one then return the smallest.
+
+    The closest is defined as the absolute difference minimized between two integers.
+
+Example 1
+
+Input: $str = "123"
+Output: "121"
+
+Example 2
+
+Input: $str = "2"
+Output: "1"
+
+There are two closest palindrome "1" and "3". Therefore we return the smallest "1".
+
+Example 3
+
+Input: $str = "1400"
+Output: "1441"
+
+Example 4
+
+Input: $str = "1001"
+Output: "999"
+
+=cut
+
+use Test2::V0;
+
+
+
+
+is(closest_palindrome(123),  121, 'Example 1');
+is(closest_palindrome(2),      1, 'Example 2');
+is(closest_palindrome(1440), 1441,'Example 3');
+is(closest_palindrome(1001), 999, 'Example 4');
+is(closest_palindrome(-123),  0,  'Example 5');
+done_testing();
+
+
+sub closest_palindrome
+{
+     my $num = $_[0];
+     my @signs = ( -1, 1);
+     my $multiplier = 1;
+     
+     my $cand = $num;
+     do
+     {
+          for my $sign ( @signs )
+          {
+               $cand = $num + $multiplier * $sign;
+               return $cand if is_palindrome($cand);
+          }
+          $multiplier++;
+     } 
+     while (1) 
+}
+
+
+
+
+sub is_palindrome
+{
+     return 0 if ( $_[0] < 0 );
+     return $_[0] eq reverse($_[0]); 
+}
+\ No newline at end of file