Find the Cat #214: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (1)Orange (9)Yellow (12)Green (12)Teal (19)Blue (11)Purple (10)Pink (14)Brown (6)Grey (6)

Every row, every column and every color region needs exactly one cat -- but no two cats may touch, not even diagonally. This puzzle is a 10x10 grid with 10 colored regions.

  • 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 Red region has only one open square left: R4C7. Put a cat there.
  2. Wherever the cat in the Orange region ends up, it rules out R5C5. Cross that square out.
  3. Wherever the cat in the Blue region ends up, it rules out R2C9. Cross that square out.
  4. Wherever the cat in the Grey region ends up, it rules out R9C9. Cross that square out.
  5. The Blue, Brown and Grey regions can only use columns 8, 9 and 10, so columns 8, 9 and 10 are already spoken for. Cross out R2C8, R5C9, R6C8, R7C8, R8C8 and R9C8.
  6. Wherever the cat in the Pink region ends up, it rules out R1C6, R2C6, R6C6, R8C5, R8C6 and R10C6. Cross those squares out.
  7. Wherever the cat in the Orange region ends up, it rules out R7C4. Cross that square out.
  8. Rows 1, 2 and 3 can only use the Green, Teal and Blue regions, so the Green, Teal and Blue regions are already spoken for. Cross out R5C1, R5C2, R5C3, R5C4, R6C2 and R7C2.
  9. Row 5 has only one open square left: R5C10. Put a cat there.
  10. Wherever the cat in the Grey region ends up, it rules out R10C1, R10C2, R10C3, R10C4 and R10C5. Cross those squares out.
  11. Wherever the cat in the Yellow region ends up, it rules out R9C3. Cross that square out.
  12. Wherever the cat in row 2 ends up, it rules out R1C2 and R3C4. Cross those squares out.
  13. Wherever the cat in row 8 ends up, it rules out R7C3. Cross that square out.
  14. The Orange and Yellow regions can only use columns 4 and 5, so columns 4 and 5 are already spoken for. Cross out R1C4, R1C5, R2C4, R2C5 and R3C5.
  15. The Green region has only one open square left: R1C3. Put a cat there.
  16. The Blue region has only one open square left: R3C9. Put a cat there.
  17. The Teal region has only one open square left: R2C1. Put a cat there.
  18. The Grey region has only one open square left: R10C8. Put a cat there.
  19. Wherever the cat in row 6 ends up, it rules out R7C5. Cross that square out.
  20. Row 7 has only one open square left: R7C6. Put a cat there.
  21. The Orange region has only one open square left: R6C4. Put a cat there.
  22. The Yellow region has only one open square left: R9C5. Put a cat there.
  23. The Purple region has only one open square left: R8C2. Put a cat there.

About this puzzle

Where to start: the Red region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Red) to 19 squares. It can be solved in 23 deduction steps using grouped row/column/region deductions.

Look for a color that sits entirely inside one row or one column. Its cat must be in that line, so every other square in that line can be crossed out.

When you fill the last cat, press Check Answer -- the grid is verified against the stored solution and any broken rule is named so you know where to look.

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