Sub-Row/Column Elimination

The numeric buttons across the top of the grid trigger highlighting. When a numeric button is clicked, the background turns red for that button & all the cells with that digit turn green. Button 1 was clicked below (red background) & all the cells with a 1 are highlighted in green.

This assists in identifying sub-blocks with a single row or column containing the target digit. In this case Row F has a single row with 1's which means only that sub-block can have a 1 in that row, see rectangle D-E/7-9. Thus the 1's in F4 & F6 can be removed.

By sequentially clicking each numeric button, each digit can be inspected & any Sub-Row/Column Eliminations can be made.

MXQ

Introduction Initial Values Start Grid Sub RC Elimination 2-Cell Chains Strange 2C Chains Swordfish Patterns Re-Check/Refresh X-Wing Patterns 7C Swordfish 4-Cell Chains (Row) 4-Cell Chains (Col) Solution Change Tracking Re-Eng. Grids

Sub-Row/Column Elimination