Bare and hidden singles are the easiest squares to resolve. A unadorned single is every time a amount can only go in a single possible cell. A concealed one is when There may be only cell for the offered prospect. ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​... https://sudoku-hard---hard-sudoku91690.gynoblog.com/26341441/detailed-notes-on-sudoku-hard-hard-sudoku