all tasks

Task/Symmetric-difference/Perl/symmetric-difference.pl

@@ -0,0 +1,17 @@
+sub symm_diff {
+        # two lists passed in as references
+        my %in_a = map(($_=>1), @{+shift});
+        my %in_b = map(($_=>1), @{+shift});
+
+        my @a = grep { !$in_b{$_} } keys %in_a;
+        my @b = grep { !$in_a{$_} } keys %in_b;
+
+        # return A-B, B-A, A xor B as ref to lists
+        return \@a, \@b, [ @a, @b ]
+}
+
+my @a = qw(John Serena Bob  Mary Serena);
+my @b = qw(Jim  Mary   John Jim  Bob   );
+
+my ($a, $b, $s) = symm_diff(\@a, \@b);
+print "A\\B: @$a\nB\\A: @$b\nSymm: @$s\n";