title: shift jis decoding/encoding in perl
body: <p>When I try decode a shift-jis encoded string and encode it back, some of the characters get garbled: 
  I have following code:</p>
  
  <pre>
  use Encode qw(decode encode);
  $val=;
  print "\nbefore decoding: $val";
  my $ustr = Encode::decode("shiftjis",$val);
  print "\nafter decoding: $ustr";
  print "\nbefore encoding: $ustr";
  $val = Encode::encode("shiftjis",$ustr);
  print "\nafter encoding: $val";
  </pre>
  
  <p>when I use a string : helloソworld in input it gets properly decoded and encoded back,i.e. before decoding and after encoding prints in above code print the same value.
  But when I tried another string like : ⅠⅡⅢⅣⅤⅥⅦⅧⅨⅩ</p>
  
  <p>The end output got garbled.</p>
  
  <p>Is it a perl library specific problem or it is a general shift jis mapping problem?
  Is there any solution for it?</p>