sbool iiSumRect_debug = true;

static double iiSumRect(double[][] ii, Rect r) {
  double bottomLeft = ii[r.y2()-1][r.x-1];
  double bottomRight = ii[r.y2()-1][r.x2()-1];
  double topLeft = ii[r.y-1][r.x-1];
  double topRight = ii[r.y-1][r.x2()-1];
  if (iiSumRect_debug)
    printVars(+topLeft, +topRight, +bottomLeft, +bottomRight);
  double lShape = bottomRight-topLeft;
  double topRightSegment = topRight-topLeft;
  double bottomLeftSegment = bottomLeft-topLeft;
  //ret -(lShape-topRightSegment-bottomLeftSegment);
  //ret bottomRight-bottomLeft-topRight+topLeft;
  ret bottomRight-topLeft-(topRight-topLeft)-(bottomLeft-topLeft);
}