This post continues a review of Will Shortz’ Hard Sudoku, v.1. with the sixth of ten pre-selected puzzles. Each one is resolved at the basic level. The detailed review requires time and patience,   but its value is the detailed examples of Sysudoku Basic, an entertaining and efficient way to prepare the grid for advanced  methods. The starting point for reading this blog is the Guide, a network of pages accessed from the menu bar above.

A tough line marking of Will Shortz’ Hard Sudoku v.1 Beware 16 ends with a hidden single.

Here’s the grid at the hidden single SWhs4. In row 7, with six cells unclaimed, only one is available for 4.

Next is Beware! Very Challenging 175.

You also might enjoy following the update posts reviewing Krazy Dad’s Insane collection, beginning in July 16, 2013. It’s the beginning of an effort to update earlier post examples based on what I think I’ve learned since.