Naked quad strategy for solving sudoku
Advanced strategies
Naked quad
We will use this technique when we have exclusively the four same candidates in the same block, line or column.
If in this area (block, line or column), the four candidates are the only present in quatres cells, they have to be eliminated from other cells of the area.
Example
Here an example of quadruple candidates.
In this line, the 1, 3, 6 and 8 are quadruple candidates. The cells are highlighted in yellow.
We can eliminate them from the other cells of the row..
Strategies list
Elimination of candidates by interaction in the same area
Elimination of candidates by interaction in several areas
Elimination of candidates by interaction in all the puzzle
[ Up ]