GridMew1Check region A
region A has only one remaining candidate: row 1, column 5. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 10 other cells.Use a top singleton to read the middle columns
Original puzzle gm-6-0046
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 A is only r1c5. Place its cat, then inspect column 4 alongside the fixed cat at r5c3. The important next observation is vertical rather than another small region.
6×6 · 1 fixed cats · 5 explained deductions. Region sizes: A: 1 · B: 12 · C: 4 · D: 12 · E: 4 · F: 3.
A deduction worth checking
Column 4 forces r3c4. This fills C, removing r3c1 and r3c2 by row and r3c6 by that same row quota.
A move to double-check · r4c1
At step 3, the new cat at r2c2 fills B. r4c1 belongs to B too, despite being far below it, so region membership explains its removal.
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 B B A D B B B B D D B B C C D D B B C C D D E E E E D D F F F D D D
Fixed cats: row 5, column 3. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check column 4
column 4 has only one remaining candidate: row 3, column 4. 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 2
column 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 3. Place one cat, then exclude 2 other cells.4Check row 4
row 4 has only one remaining candidate: row 4, column 6. 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 6
row 6 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 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: r1c5, r2c2, r3c4, r4c6, r5c3, r6c1.
Try another puzzle
A bottom-left singleton opens a distant column
gm-6-0009 · 6×6 · practice
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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.
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