What about a bad 'N/A' with or without digits?

c:\@Work\Perl\monks>perl -wMstrict -e
"for (
   '1234 5678 no_nas_here blah blah',
   '1234 N/A should_be_na2 blah blah',
   'N/A 5678 must_be_na1 blah blah',
   'N/A N/A nana',
   'foo 9999 fake_nas_1 blah',
   '9999 foo fake_nas_2 blah blah',
   'foo foo fake_nas_3 blah blah blah',
   ) {
   my @flds = split;
   if ( $flds[0].$flds[1] eq 'N/AN/A' ) {
     print \"nana: $flds[2]\n\";
       }
     elsif ( $flds[0] eq 'N/A' ) {
       print \"na1: $flds[2]\n\";
       }
     elsif ( $flds[1] eq 'N/A' ) {
       print \"na2: $flds[2]\n\";
       }
     else {
       print \"no na: $flds[2]\n\";
       }
   }
"
no na: no_nas_here
na2: should_be_na2
na1: must_be_na1
nana: nana
no na: fake_nas_1
no na: fake_nas_2
no na: fake_nas_3
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