GridMew1Check region E
region E has only one remaining candidate: row 5, column 7. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 11 other cells.Walk the narrow right-side regions before scanning rows
Original puzzle gm-8-0053
By GridMew · Published 15 October 2026 · Updated 16 October 2026
8 × 8 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.
The given at r2c8 leaves E with r5c7. Filling E then reduces D to r4c5, and A subsequently resolves at r1c6. Follow those small regions before attacking the large C and G areas.
8×8 · 1 fixed cats · 7 explained deductions. Region sizes: A: 4 · B: 8 · C: 18 · D: 3 · E: 3 · F: 2 · G: 18 · H: 8.
A deduction worth checking
F resolves at r6c1. Besides occupying column 1, it rules out r7c2 by contact and prepares the last two rows.
A move to double-check · r7c2
r7c2 is in H, not F, but it is a corner neighbor of r6c1. Distinguish a regional boundary from the no-touch boundary around a cat.
Green marks the cell being discussed, not a cat to place. This is the position before step 4; 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.
C C C C A A B B C C C C A A B B C C C C C C B B C C C C D D B B F G G G D G E E F G G G G G G E H H H G G G G G H H H H H G G G
Fixed cats: row 2, column 8. One cat is required in each row, column and region.
Step-by-step walkthrough
2Check region D
region D has only one remaining candidate: row 4, column 5. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 2. Place one cat, then exclude 11 other cells.3Check region A
region A has only one remaining candidate: row 1, column 6. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 3. Place one cat, then exclude 6 other cells.4Check 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 4. Place one cat, then exclude 7 other cells.5Check region G
region G has only one remaining candidate: row 7, column 4. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 5. Place one cat, then exclude 3 other cells.6Check row 8
row 8 has only one remaining candidate: row 8, column 2. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 6. Place one cat, then exclude 1 other cells.7Check row 3
row 3 has only one remaining candidate: row 3, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 7. 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: r1c6, r2c8, r3c3, r4c5, r5c7, r6c1, r7c4, r8c2.
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