Divide the grid into nine orthogonally-connected regions, each containing nine cells. Each row, column and region must contain the digits 1 to 9, once each. A clue outside the grid indicates that the first X cells in the row/column from that direction are in the same region, with X being the digit in the first cell. Moreover, the next cell (the (X+1)th cell) is part of a different region. The clue further indicates the sum of the digits in those X cells. In some cases, the clue has been replaced by a question mark, which stands for any single- or double-digit number.