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diff --git a/challenge-253/jo-37/perl/ch-2.pl b/challenge-253/jo-37/perl/ch-2.pl
new file mode 100755
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+++ b/challenge-253/jo-37/perl/ch-2.pl
@@ -0,0 +1,75 @@
+#!/usr/bin/perl -s
+
+use v5.24;
+use Test2::V0 '!float';
+use PDL;
+use PDL::NiceSlice;
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV;
+usage: $0 [-examples] [-tests] [M]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+M
+    a matrix in any form accepted by the PDL string constructor,
+    e.g.
+    "[[1, 2, 0, 0, 4], [1, 1, 1, 1, 0], [3, 0, 0, 0, 0]]"
+EOS
+
+
+### Input and Output
+
+say weakest("@ARGV");
+
+
+### Implementation
+
+sub weakest {
+	my $m = pdl @_;
+    $m->append($m((0))->ndcoords)->qsortveci;
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is weakest([
+                   [1, 1, 0, 0, 0],
+                   [1, 1, 1, 1, 0],
+                   [1, 0, 0, 0, 0],
+                   [1, 1, 0, 0, 0],
+                   [1, 1, 1, 1, 1]
+                 ])->unpdl, [2, 0, 3, 1, 4], 'example 1';
+
+        is weakest([
+                   [1, 0, 0, 0],
+                   [1, 1, 1, 1],
+                   [1, 0, 0, 0],
+                   [1, 0, 0, 0]
+                 ])->unpdl, [0, 2, 3, 1], 'example 2';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+
+        is weakest([0, 1, 2, 3],
+                   [1, 0, 0, 0],
+                   [1, 2, 3, 4],
+                   [0, 1, 2, 3],
+                   [1, 2, 3, 5])->unpdl, [0, 3, 1, 2, 4], 'arbitrary matrix';
+	}
+
+    done_testing;
+    exit;
+}