Find the Cat #265: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (9)Orange (8)Yellow (1)Green (6)Teal (19)Blue (18)Purple (13)Pink (8)Brown (10)Grey (8)

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: R9C1. Put a cat there.
  2. Wherever the cat in the Green region ends up, it rules out R10C3, R10C4, R10C5 and R10C6. Cross those squares out.
  3. Wherever the cat in the Purple region ends up, it rules out R7C4. Cross that square out.
  4. Wherever the cat in the Red region ends up, it rules out R4C5. Cross that square out.
  5. Wherever the cat in the Brown region ends up, it rules out R7C7. Cross that square out.
  6. Rows 1, 2 and 3 can only use the Teal, Blue and Grey regions, so the Teal, Blue and Grey regions are already spoken for. Cross out R4C2, R4C3, R4C4, R4C9, R5C2, R5C3 and 3 more.
  7. Wherever the cat in column 2 ends up, it rules out R1C3, R1C4, R2C3, R2C4 and R3C4. Cross those squares out.
  8. Wherever the cat in column 4 ends up, it rules out R6C3, R7C3, R7C5 and R8C3. Cross those squares out.
  9. Column 3 has only one open square left: R3C3. Put a cat there.
  10. The Blue region has only one open square left: R1C2. Put a cat there.
  11. Wherever the cat in column 5 ends up, it rules out R4C6, R4C7, R4C8 and R5C6. Cross those squares out.
  12. Row 4 has only one open square left: R4C10. Put a cat there.
  13. The Grey region has only one open square left: R2C9. Put a cat there.
  14. Wherever the cat in row 5 ends up, it rules out R6C6. Cross that square out.
  15. Wherever the cat in row 7 ends up, it rules out R6C7, R8C6, R8C7 and R8C8. Cross those squares out.
  16. Column 6 has only one open square left: R7C6. Put a cat there.
  17. The Red region has only one open square left: R5C5. Put a cat there.
  18. The Orange region has only one open square left: R6C8. Put a cat there.
  19. The Green region has only one open square left: R10C7. Put a cat there.
  20. The Purple region has only one open square left: R8C4. 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 19 squares. It can be solved in 20 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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