Queens Gamers

Learn a deduction, then use it

Queens Forced Placement: Single Position

A forced placement is a cell that is the only remaining candidate in one row, column or region. It is a logical conclusion, not a guess from the answer.

Every figure below is a real, verified intermediate position. Dots are remaining candidates; × cells were excluded by earlier deductions. A white outline shows the deduction’s focus.

Three worked examples

Example 1

Region 1 has one candidate left. Every group needs one Queen, so R1C7 is forced.

Position after 0 verified deductions on 7×7 puzzle #1.

Before the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
After the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
Play the complete original puzzle

Example 2

Row 2 has one candidate left. Every group needs one Queen, so R2C1 is forced.

Position after 5 verified deductions on 7×7 puzzle #1.

Before the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
After the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
Play the complete original puzzle

Example 3

Column 6 has one candidate left. Every group needs one Queen, so R4C6 is forced.

Position after 4 verified deductions on 7×7 puzzle #9.

Before the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
After the deduction. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.
Play the complete original puzzle

A tempting mistake

Row 1 still has 7 candidates. Choosing R1C1 now is a guess, not a forced placement.

Counterexample: no candidates have been eliminated. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.

Try the deduction yourself

In row 3, select the only remaining candidate. This position follows 5 verified deductions.

Technique exercise. Rows run top to bottom; columns left to right. Numbers identify regions; × means excluded.

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