Other unrelated stuff:

my $evens = "";
$evens .= substr($mixed_string, ($_ * 2), 1) foreach (0..length($mixed
+_string) / 2);

my $odds = "";
$odds .= substr($mixed_string, ($_ * 2 + 1), 1) foreach (0..length($mi
+xed_string) / 2 - 1);
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