Can anyone explain the following behaviour? When I run the script below the results of bracket matches are different: "1 2" and "12" 
$_ = '123';

if(/(1|12)(2?)/)
{
  print "$1 $2\n";
}

if(/(12|1)(2?)/)
{
  print "$1 $2\n";
}

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In reply to brackets matching problem by lucky8

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