private static void cartPr(Set<Long> keys, List<Pointer> t) throws JWNLException {
   for (int i = 0; i < t.size(); i++) {
     Pointer ps = t.get(i);
     long sourceOffset = ps.getTargetSynset().getOffset();
     for (int j = i + 1; j < t.size(); j++) {
       Pointer pt = t.get(j);
       long targetOffset = pt.getTargetSynset().getOffset();
       if (sourceOffset != targetOffset) {
         long key;
         if (targetOffset > sourceOffset) {
           key = (targetOffset << 32) + sourceOffset;
         } else {
           key = (sourceOffset << 32) + targetOffset;
         }
         keys.add(key);
       }
     }
   }
 }