Find the Cat #223: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (11)Orange (6)Yellow (10)Green (16)Teal (7)Blue (10)Purple (18)Pink (1)Brown (11)Grey (10)

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 Pink region has only one open square left: R10C10. Put a cat there.
  2. Wherever the cat in the Orange region ends up, it rules out R3C2. Cross that square out.
  3. Wherever the cat in the Brown region ends up, it rules out R7C8, R8C7 and R8C8. Cross those squares out.
  4. The Red and Brown regions can only use rows 8 and 9, so rows 8 and 9 are already spoken for. Cross out R8C3, R8C4, R8C5, R8C6, R9C4, R9C5 and 2 more.
  5. The Red, Orange and Teal regions can only use columns 1, 2 and 3, so columns 1, 2 and 3 are already spoken for. Cross out R1C1, R1C2, R1C3, R2C3, R3C3, R4C3 and 2 more.
  6. The Blue region has only one open square left: R1C4. Put a cat there.
  7. Wherever the cat in the Grey region ends up, it rules out R2C1, R2C2, R2C7 and R2C8. Cross those squares out.
  8. Wherever the cat in the Orange region ends up, it rules out R5C1. Cross that square out.
  9. Wherever the cat in column 3 ends up, it rules out R8C2. Cross that square out.
  10. Wherever the cat in column 5 ends up, it rules out R3C6, R3C7, R3C8, R4C6, R4C7 and R4C8. Cross those squares out.
  11. Wherever the cat in column 7 ends up, it rules out R6C6 and R6C8. Cross those squares out.
  12. The Green and Teal regions can only use rows 6 and 7, so rows 6 and 7 are already spoken for. Cross out R6C5, R6C7 and R7C5.
  13. Rows 3, 4, 6 and 8 can only use columns 1, 2, 5 and 9, so columns 1, 2, 5 and 9 are already spoken for. Cross out R2C9, R5C2, R5C5, R5C9, R7C1, R7C2 and 3 more.
  14. The Grey region has only one open square left: R2C6. Put a cat there.
  15. The Purple region has only one open square left: R4C5. Put a cat there.
  16. The Orange region has only one open square left: R3C1. Put a cat there.
  17. The Red region has only one open square left: R9C3. Put a cat there.
  18. The Teal region has only one open square left: R6C2. Put a cat there.
  19. The Green region has only one open square left: R7C7. Put a cat there.
  20. The Yellow region has only one open square left: R5C8. Put a cat there.
  21. The Brown region has only one open square left: R8C9. Put a cat there.

About this puzzle

Where to start: the Pink region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Pink) to 18 squares. It can be solved in 21 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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