GridMew1Check region F
region F has only one remaining candidate: row 6, column 1. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 9 other cells.A bottom-left singleton opens a distant column
Original puzzle gm-6-0009
By GridMew · Published 15 October 2026 · Updated 16 October 2026
6 × 6 practice
Read the starting position, follow the deductions, and check the move that is easy to misread.
Puzzle board · starting state
How to approach this board
Coordinates such as r2c3 mean row 2, column 3. Count rows from the top and columns from the left.
Region F forces r6c1. Alongside the r3c5 given, it leaves region E with just r5c6. These edge placements matter because they clear whole columns as well as local neighborhoods.
6×6 · 1 fixed cats · 5 explained deductions. Region sizes: A: 8 · B: 4 · C: 4 · D: 13 · E: 6 · F: 1.
A deduction worth checking
Column 4 then resolves at r1c4. That cat removes r2c3 by touching, helping row 2 settle at r2c2.
A move to double-check · r2c3
r2c3 cannot be kept as a second option after r1c4. Their different labels do not override the immediate diagonal prohibition.
Green marks the cell being discussed, not a cat to place. This is the position before step 3; compare the deduction below.
Read the starting board as text
Each line is one row, left to right. Matching letters belong to the same connected region.
B B A A A A D B A A A A D B D C C C D D D E E C D D D D E E F D D D E E
Fixed cats: row 3, column 5. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check region E
region E has only one remaining candidate: row 5, column 6. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 2. Place one cat, then exclude 3 other cells.3Check column 4
column 4 has only one remaining candidate: row 1, column 4. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 3. Place one cat, then exclude 3 other cells.4Check row 2
row 2 has only one remaining candidate: row 2, column 2. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 4. Place one cat, then exclude 1 other cells.5Check row 4
row 4 has only one remaining candidate: row 4, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 5. Place one cat, then exclude 0 other cells.Show solution · reveals all cat positions
The final cats satisfy every row, column and region quota, with no edge or corner contact.
Cat positions: r1c4, r2c2, r3c5, r4c3, r5c6, r6c1.
Try another puzzle
Two small upper regions steer the lower rows
gm-6-0027 · 6×6 · practice
Practice single-candidate placements on another 6×6 board.
Read this walkthrough →Clear the bottom row, then work upward
gm-5-0029 · 5×5 · practice
Transfer single-candidate placements to a 5×5 grid; compare how the candidates change.
Read this walkthrough →Two possible cats, one shared exclusion
gm-5-0001 · 5×5 · challenge
Compare this route with shared-neighbor exclusions, and check why that different rule is needed.
Read this walkthrough →