Find the Cat #230: 10x10 Grid Puzzle (Hard)

hard

Tap a square: ✕ (ruled out) → 🐱 (cat) → clear

0 / 10 cats · 0:00
Red (16)Orange (1)Yellow (11)Green (12)Teal (9)Blue (7)Purple (4)Pink (7)Brown (12)Grey (21)

Find the 10 hidden cats. Each row, each column and each colored region holds exactly one, and cats never sit on neighboring squares, diagonals included.

  • One cat in every row and every column.
  • One cat in every color region.
  • Cats can’t touch — not even diagonally.

Step-by-step solution

Squares are written as R<row>C<column>, counting from the top-left. Cross out the squares listed, and place a cat wherever a step says so.

  1. The Orange region has only one open square left: R4C1. Put a cat there.
  2. Wherever the cat in the Purple region ends up, it rules out R9C2, R9C3, R10C4, R10C5, R10C6, R10C7 and 3 more. Cross those squares out.
  3. Wherever the cat in the Pink region ends up, it rules out R7C3. Cross that square out.
  4. The Purple and Pink regions can only use columns 2 and 3, so columns 2 and 3 are already spoken for. Cross out R1C2, R1C3, R2C2, R2C3, R3C3, R5C3 and 2 more.
  5. Wherever the cat in the Red region ends up, it rules out R1C4, R2C4, R6C4, R7C4, R8C4 and R9C4. Cross those squares out.
  6. The Teal region has only one open square left: R8C5. Put a cat there.
  7. The Yellow region has only one open square left: R3C6. Put a cat there.
  8. The Red region has only one open square left: R5C4. Put a cat there.
  9. The Pink region has only one open square left: R7C2. Put a cat there.
  10. The Purple region has only one open square left: R10C3. Put a cat there.
  11. The Brown region has only one open square left: R6C7. Put a cat there.
  12. The Green region has only one open square left: R1C8. Put a cat there.
  13. The Blue region has only one open square left: R2C10. Put a cat there.
  14. The Grey region has only one open square left: R9C9. Put a cat there.

About this puzzle

Where to start: the Orange region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Orange) to 21 squares. It can be solved in 14 deduction steps using grouped row/column/region deductions.

A useful habit is to mark squares you have ruled out. Tap a square once for a cross and twice for a cat -- crosses cost nothing and make later deductions much easier to spot.

This is a variation of the Star Battle family of grid puzzles, sometimes also called Queens-style puzzles, with cats in place of stars.

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