public boolean compatible(int begin,int end){
  if (begin >= firstZero) {
    BitSet pattern=new BitSet();
    pattern.set(begin - firstZero,end - firstZero);
    return !bits.intersects(pattern);
  }
  return false;
}

public boolean compatible ( int begin , int end ) { if ( begin >= firstZero ) { BitSet pattern = new BitSet ( ) ; pattern . set ( begin - firstZero , end - firstZero ) ; return ! bits . intersects ( pattern ) ; } return false ; }
tests whether a new range is compatible with the current coverage vector . it must be after the first uncovered word , obviously , and must not conflict with spans after the first uncovered word .
