Halved Squares Sudoku (405)

Place a digit from 1-9 in each empty cell in the grid such that each row, column and marked region contains each digit exactly once. Some cells are halved by one of the diagonals. For any such cell, exactly one of its two halves shall contain a digit. That digit is considered to belong to the row and column containing its cell, as well as to the region connected to the half cell the digit is in.

Reference: WPF (1)