Find the Cat #283: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (17)Orange (11)Yellow (1)Green (18)Teal (7)Blue (10)Purple (8)Pink (14)Brown (10)Grey (4)

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 Yellow region has only one open square left: R3C3. Put a cat there.
  2. Wherever the cat in the Blue region ends up, it rules out R1C5. Cross that square out.
  3. Wherever the cat in column 10 ends up, it rules out R9C9. Cross that square out.
  4. The Pink and Brown regions can only use columns 1 and 2, so columns 1 and 2 are already spoken for. Cross out R1C2.
  5. The Blue region has only one open square left: R4C5. Put a cat there.
  6. The Grey region has only one open square left: R6C4. Put a cat there.
  7. Wherever the cat in the Purple region ends up, it rules out R1C6, R2C6, R7C6, R8C6, R9C7 and R10C7. Cross those squares out.
  8. Wherever the cat in the Orange region ends up, it rules out R1C7, R2C7, R5C7, R7C8 and R8C8. Cross those squares out.
  9. The Teal and Purple regions can only use rows 9 and 10, so rows 9 and 10 are already spoken for. Cross out R9C1, R9C2, R10C1 and R10C2.
  10. Wherever the cat in the Brown region ends up, it rules out R1C1, R2C1, R5C1, R7C2 and R8C2. Cross those squares out.
  11. The Pink region has only one open square left: R5C2. Put a cat there.
  12. Wherever the cat in the Red region ends up, it rules out R1C8, R1C9 and R2C10. Cross those squares out.
  13. Row 1 has only one open square left: R1C10. Put a cat there.
  14. The Red region has only one open square left: R2C8. Put a cat there.
  15. The Teal region has only one open square left: R10C9. Put a cat there.
  16. The Purple region has only one open square left: R9C6. Put a cat there.
  17. The Orange region has only one open square left: R7C7. Put a cat there.
  18. The Brown region has only one open square left: R8C1. Put a cat there.

About this puzzle

Where to start: the Yellow region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Yellow) to 18 squares. It can be solved in 18 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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