Rules of 9x9 Odd/Even Sudoku
Place a digit from 1 to 9 in each empty cell so that each digit appears exactly once in each row, column outlined region.
Additionally, all the cells which can contain the odd/even numbers are greyed.
Even-Odd Sudoku: fill in the grid so that every row, every column, and every 3 x 3 box contains the digits 1 through 9. Cells with gray circles must contain odd digits, cells with gray squares must contain even digits.