int[] calculateRelative(int[] absolute){
  int[] res=new int[absolute.length];
  res[0]=absolute[0];
  for (int i=1; i < res.length; i++) {
    res[i]=absolute[i] - absolute[i - 1];
  }
  return res;
}

int [ ] calculateRelative ( int [ ] absolute ) { int [ ] res = new int [ absolute . length ] ; res [ 0 ] = absolute [ 0 ] ; for ( int i = 1 ; i < res . length ; i ++ ) { res [ i ] = absolute [ i ] - absolute [ i - 1 ] ; } return res ; }
calcuates the relative offset
