Sole Candidate Technique Explained

Hi Everyone,

The sole candidate technique (also called naked-single) is one of the simplest techniques, and you are possibly using it without even realising.

Basically:

When all the other possibilities for the sudoku cell have been removed, and only one choice remains - then it must be the correct value.

Check out this example:

As you can see, if you follow the 3 rules of sudoku, then there is only one possibility for the green square:

The numbers 1 to 9 must occur only once;

So the only number left (the sole candidate) is 6.

Cheers

Gath