Find the Cat #259: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (1)Orange (4)Yellow (12)Green (15)Teal (15)Blue (10)Purple (11)Pink (10)Brown (11)Grey (11)

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 Red region has only one open square left: R7C8. Put a cat there.
  2. Wherever the cat in the Orange region ends up, it rules out R9C2. Cross that square out.
  3. The Orange, Purple and Brown regions can only use rows 8, 9 and 10, so rows 8, 9 and 10 are already spoken for. Cross out R8C1, R8C2, R8C5, R8C6, R9C1, R9C6 and 1 more.
  4. Wherever the cat in the Teal region ends up, it rules out R5C3, R5C4, R6C1, R6C2, R6C5, R6C6 and 1 more. Cross those squares out.
  5. Wherever the cat in the Pink region ends up, it rules out R5C9. Cross that square out.
  6. Wherever the cat in column 1 ends up, it rules out R4C2. Cross that square out.
  7. The Blue and Brown regions can only use columns 9 and 10, so columns 9 and 10 are already spoken for. Cross out R2C9, R3C9 and R4C9.
  8. The Pink region has only one open square left: R5C7. Put a cat there.
  9. The Grey region has only one open square left: R4C3. Put a cat there.
  10. The Orange region has only one open square left: R10C2. Put a cat there.
  11. The Teal region has only one open square left: R6C4. Put a cat there.
  12. The Purple region has only one open square left: R9C5. Put a cat there.
  13. The Brown region has only one open square left: R8C10. Put a cat there.
  14. The Blue region has only one open square left: R1C9. Put a cat there.
  15. The Yellow region has only one open square left: R3C6. Put a cat there.
  16. The Green region has only one open square left: R2C1. Put a cat there.

About this puzzle

Where to start: the Red region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Red) to 15 squares. It can be solved in 16 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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