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$ perl -E 'say sprintf "%02x", ord $;'
1c

$ perl -E 'use Data::Dump; my (%h, $x); for my $i (0,1) { for my $j (0
+,1) { $h{$i,$j} = $x++ } } dd \%h; say for sort keys %h'
{ "0\x1C0" => 0, "0\x1C1" => 1, "1\x1C0" => 2, "1\x1C1" => 3 }
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