Mirrored from Sudopedia, the Free Sudoku Reference Guide

Reverse BUG Lite

The Reverse BUG Lite is a generalization of the Reverse BUG solving technique. It can be stated as follows:

In solving a sudoku with a unique solution, it is not possible to have two rows or columns partially filled so that all filled digits together form an unavoidable set.

The reason is because the unfilled cells in these two rows or columns also form an unavoidable set.

Example

If rows 1 and 2 look like this: 

1 . . | 2 . . | 3 . .
3 . . | 1 . . | . . .

Then R2C7 <> 2.

Reference

See Also

This page was last modified 22:49, 26 August 2009.