Find the Cat #249: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (10)Orange (14)Yellow (8)Green (10)Teal (12)Blue (11)Purple (1)Pink (14)Brown (13)Grey (7)

Can you place all 10 cats? One per row, one per column, one per color -- and keep them at least one square apart in every direction.

  • 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 Purple region has only one open square left: R2C4. Put a cat there.
  2. Wherever the cat in the Grey region ends up, it rules out R3C2, R4C1, R4C5, R4C6, R4C7, R4C8 and 4 more. Cross those squares out.
  3. Wherever the cat in the Yellow region ends up, it rules out R5C9. Cross that square out.
  4. The Red and Green regions can only use rows 1 and 3, so rows 1 and 3 are already spoken for. Cross out R1C9, R1C10, R3C8, R3C9 and R3C10.
  5. Wherever the cat in the Yellow region ends up, it rules out R5C1, R5C6, R5C8, R5C10 and R6C6. Cross those squares out.
  6. Wherever the cat in the Pink region ends up, it rules out R6C7, R6C9 and R7C9. Cross those squares out.
  7. Wherever the cat in column 9 ends up, it rules out R7C10, R8C10, R9C8, R9C10, R10C5, R10C6 and 3 more. Cross those squares out.
  8. Column 10 has only one open square left: R6C10. Put a cat there.
  9. The Red and Blue regions can only use columns 1 and 2, so columns 1 and 2 are already spoken for. Cross out R4C2, R7C2, R8C2 and R10C2.
  10. The Grey region has only one open square left: R4C3. Put a cat there.
  11. The Teal region has only one open square left: R9C5. Put a cat there.
  12. The Yellow region has only one open square left: R5C7. Put a cat there.
  13. Column 2 has only one open square left: R1C2. Put a cat there.
  14. The Green region has only one open square left: R3C6. Put a cat there.
  15. The Brown region has only one open square left: R8C8. Put a cat there.
  16. The Orange region has only one open square left: R10C9. Put a cat there.
  17. The Blue region has only one open square left: R7C1. Put a cat there.

About this puzzle

Where to start: the Purple region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Purple) to 14 squares. It can be solved in 17 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.

Every puzzle on this site has exactly one solution that can be reached by pure deduction. If you find yourself guessing, look again for a region or line with only a few open squares left.

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