SUDOKU HARD - HARD SUDOKU FUNDAMENTALS EXPLAINED

Naked and concealed singles are the easiest squares to unravel. A naked solitary is whenever a variety can only go in one attainable mobile. A concealed single is when You can find only cell for your given applicant.If you would like enter a pencil mark, click on/contact the square you should set in the pencil mark. It'll change light-weight blue.