[![BBC Regular Expression Puzzle][1]][1] [1]: https://i.sstatic.net/jZfaY.jpg Rather than use traditional hints, each square must be a match of the regular expression associated with the row or column. >! [Source](http://www.bbc.co.uk/programmes/articles/5LCB3rN2dWLqsmGMy5KYtBf/puzzle-for-today)