In a Kakuro puzzle, the digits 2–9 are used to fill the white squares without repetition in an entry. The product of the numbers in each entry equals the clue (in gray). The clue for columns is a number above the column in the lower half of a gray square; the clue for a row is a number to the left of the row in the upper half of a gray square. For the clue "16" and a line of two white squares, the answer could be "2 8" or "8 2", but not "4 4" because that would repeat the "4".