Can anyone explain the codes below?

# Code1
@s = sort mycriteria @a;
sub mycriteria {
  my($aa) = $a =~ /(\d+)/;
  my($bb) = $b =~ /(\d+)/;
  sin($aa) <=> sin($bb) ||
  $aa*$aa <=> $bb*$bb;
}

[download]
# Code2
@s = sort {($a =~ /(\d+)/)[0] <=> ($b =~ /(\d+)/)[0] || uc($a) cmp uc(
+$b)} @a;

[download]

How the regular expressions function in the code above??

In reply to Questions on sort by jiashiun

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