Find the Cat #286: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (4)Orange (4)Yellow (20)Green (17)Teal (10)Blue (9)Purple (8)Pink (8)Brown (19)Grey (1)

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 Grey region has only one open square left: R3C3. Put a cat there.
  2. The Orange region has only one open square left: R2C10. Put a cat there.
  3. Wherever the cat in the Red region ends up, it rules out R9C5. Cross that square out.
  4. Wherever the cat in the Purple region ends up, it rules out R1C4, R1C5, R1C6, R1C7 and R1C8. Cross those squares out.
  5. Wherever the cat in the Yellow region ends up, it rules out R4C7 and R5C5. Cross those squares out.
  6. Wherever the cat in column 8 ends up, it rules out R9C9. Cross that square out.
  7. The Red, Teal, Blue and Pink regions can only use rows 7, 8, 9 and 10, so rows 7, 8, 9 and 10 are already spoken for. Cross out R7C1, R7C2, R7C6, R7C8, R7C9, R8C1 and 1 more.
  8. The Green, Blue, Purple and Pink regions can only use columns 1, 2, 4 and 5, so columns 1, 2, 4 and 5 are already spoken for. Cross out R4C5.
  9. Wherever the cat in the Yellow region ends up, it rules out R5C7, R6C6, R8C6, R9C6 and R10C6. Cross those squares out.
  10. The Red region has only one open square left: R9C7. Put a cat there.
  11. The Teal region has only one open square left: R10C9. Put a cat there.
  12. Wherever the cat in the Blue region ends up, it rules out R6C5 and R8C4. Cross those squares out.
  13. The Pink region has only one open square left: R8C2. Put a cat there.
  14. The Purple region has only one open square left: R1C1. Put a cat there.
  15. Column 5 has only one open square left: R7C5. Put a cat there.
  16. The Green region has only one open square left: R5C4. Put a cat there.
  17. The Yellow region has only one open square left: R4C6. Put a cat there.
  18. The Brown region has only one open square left: R6C8. Put a cat there.

About this puzzle

Where to start: the Grey region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Grey) to 20 squares. It can be solved in 18 deduction steps using grouped row/column/region deductions.

If a row and a color both have only two open squares and share them, those two lines are locked together -- neither can use squares anywhere else.

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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