Find the Cat #298: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (14)Orange (13)Yellow (20)Green (1)Teal (13)Blue (11)Purple (9)Pink (7)Brown (8)Grey (4)

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 Green region has only one open square left: R10C10. Put a cat there.
  2. Wherever the cat in the Teal region ends up, it rules out R7C9. Cross that square out.
  3. Wherever the cat in the Grey region ends up, it rules out R1C1, R2C1, R3C1, R4C1, R5C1, R6C1 and 3 more. Cross those squares out.
  4. Wherever the cat in the Red region ends up, it rules out R9C5 and R9C7. Cross those squares out.
  5. Wherever the cat in the Brown region ends up, it rules out R7C8. Cross that square out.
  6. Wherever the cat in the Teal region ends up, it rules out R5C9. Cross that square out.
  7. Wherever the cat in column 2 ends up, it rules out R2C3. Cross that square out.
  8. The Red and Grey regions can only use rows 8 and 9, so rows 8 and 9 are already spoken for. Cross out R8C3, R8C4, R8C5, R8C7, R8C8 and R8C9.
  9. Wherever the cat in the Brown region ends up, it rules out R1C7, R2C7, R3C7, R4C7, R5C7, R6C6 and 2 more. Cross those squares out.
  10. Wherever the cat in the Teal region ends up, it rules out R2C9, R3C9 and R4C9. Cross those squares out.
  11. Wherever the cat in the Pink region ends up, it rules out R4C8, R5C8 and R9C8. Cross those squares out.
  12. Wherever the cat in the Purple region ends up, it rules out R1C6, R2C6, R4C5, R4C6, R8C6 and R9C6. Cross those squares out.
  13. Row 8 has only one open square left: R8C1. Put a cat there.
  14. Wherever the cat in row 4 ends up, it rules out R2C2, R2C4, R3C3, R5C2, R5C3, R5C4 and 3 more. Cross those squares out.
  15. Row 5 has only one open square left: R5C6. Put a cat there.
  16. The Brown region has only one open square left: R7C7. Put a cat there.
  17. The Blue region has only one open square left: R6C4. Put a cat there.
  18. The Red region has only one open square left: R9C3. Put a cat there.
  19. The Yellow region has only one open square left: R4C2. Put a cat there.
  20. The Teal region has only one open square left: R1C9. Put a cat there.
  21. The Pink region has only one open square left: R3C8. Put a cat there.
  22. The Orange region has only one open square left: R2C5. Put a cat there.

About this puzzle

Where to start: the Green region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Green) to 20 squares. It can be solved in 22 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.

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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