40- XV Sudoku

XV Sudoku

(Czech Republic Puzzle Championship 2014 (Sudoku Round))

Place a digit from 1 to 9 into each of the empty squares so that each digit appears exactly once in each row, column and 3x3 box. All adjacent cells with two digits summing to 5 are marked by V, while those summing to 10 are marked by X. The cells edges which do not contain a V or an X cannot have digits summing to 5 or 10.