Normal sudoku rules apply. An arrow starts its growth from a cell with a circle and spreads out from there in the form of a path which is one-cell wide and neither crosses nor touches itself orthogonally. The digits on the path (without the circle) must add up to the number in the circle. Two-digit numbers in a circle are read from left to right and the arrow can start from the 'ones' digit or the 'tens' digit. All circles are given and two arrows must not intersect anywhere. A white cell must be part of exactly one arrow; a blue cell cannot contain an arrow; and an orange cell can be part of an arrow or not.