Find Unique Possibilities

After reducing the block with possibilities, every cell in the block will have a set of possible values. In that, if a particular possible value is present only in a single cell. Then that value is the unique possible value for the cell in that block and the cell is assigned with that value.

An illustration for the above concept.

Since the value 5 is present only in the single cell,it is the unique possible value for that cell in the block. Therefore, that cell is assigned with that unique value.

Figure: A Rectangular-Block from 9x9 sudoku.

Algorithm Links

• Reducing Block Possibilities
• Finding Unique Possibilities
• Block Overlap Reduction
• Repeated Possibility Reduction
• Combined Possibility Reduction
• Apply Possibility Reduction

Consecutive Sudoku Algorithms

• Apply Consecutive Constraint
• Consecutive Chain Min-Max Reduction
• Consecutive Chain Neighbor Reduction

Greater Sudoku Algorithms

• Apply Greater Sudoku Constraint
• Greater Sudoku Neighbor Reduction
• Greater Sudoku Graph Reduction