GridMew1Check region F
region F has only one remaining candidate: row 6, column 3. Every other cell is excluded by earlier placements or deductions. Place the cat here.
Before step 1. Place one cat, then exclude 4 other cells.A shared neighborhood settles the right edge
Original puzzle gm-6-0007
By GridMew · Published 15 October 2026 · Updated 16 October 2026
6 × 6 challenge
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 givens leave region F with only r6c3. After placing it, column 5 has two top candidates. Their joint neighborhood supplies information even though neither can yet be chosen.
6×6 · 2 fixed cats · 5 explained deductions. Region sizes: A: 3 · B: 14 · C: 12 · D: 2 · E: 2 · F: 3.
A deduction worth checking
Both r1c5 and r2c5 touch r1c6 and r2c6. Removing those two column-6 candidates makes r3c6 the next single.
A move to double-check · r1c6
Do not choose r1c5 merely to exclude r1c6. The alternative r2c5 also touches that cell, which is why the elimination is already certain.
Green marks the cell being discussed, not a cat to place. This is the position before step 2; 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 A A A B B B C C C B B B C C C B B D D C C E B B B C C E F F F C C
Fixed cats: row 5, column 1; row 4, column 4. One cat is required in each row, column and region.
Step-by-step walkthrough
2Exclude common neighbors
The cat in column 5 must occupy one of row 1, column 5; row 2, column 5. Each of row 1, column 6; row 2, column 6 touches every candidate, so none can hold a cat.
Before step 2. Exclude 2 cells; then scan for a new single.3Check column 6
column 6 has only one remaining candidate: row 3, column 6. 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 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 1
row 1 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 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, r3c6, r4c4, r5c1, r6c3.
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