Friday Puzzles #260

Numbers placed in marked adjacent cells must be of opposite parity (i.e. one is odd, the other is even).  Please note that not all such cells are marked!

The trouble with if and only if conditions is that most of the fun is hidden behind the "only if" condition (think consecutive, XV, tens and so on).  These constraints still make for interesting puzzles simply as "if" constraints when designed properly.  They certainly look better.

Enjoy!

    #299 Parity Sudoku – rated medium

All puzzles © Tom Collyer 2009-14.