question: public static void onesI ( long [ ] v , int bits ) { final int fillWords = bits > > > LONG_LOG2_SIZE ; final int fillBits = bits & LONG_LOG2_MASK ; Arrays . fill ( v , 0 , fillWords , LONG_ALL_BITS ) ; v [ fillWords ] = ( 1L << fillBits ) - 1 ; Arrays . fill ( v , fillWords + 1 , v . length , 0L ) ; }
target:  Fill a vector initialized with "bits" ones.