code: protected int newestStamp(int first, int last, int bestStampSoFar) {
          int bestStamp = bestStampSoFar;
          for (int i=first; i<=last; ++i) {
              if (stamp[i] > bestStamp) {
                  bestStamp = stamp[i];
              }
          }
          return bestStamp;
      }
docs: Returns the newest stamp of a given range of fields.