Find the Cat #225: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (1)Orange (5)Yellow (9)Green (17)Teal (5)Blue (5)Purple (12)Pink (18)Brown (15)Grey (13)

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: R7C6. Put a cat there.
  2. Wherever the cat in the Orange region ends up, it rules out R1C1, R1C2, R1C3, R1C4, R1C8, R1C9 and 1 more. Cross those squares out.
  3. Wherever the cat in the Yellow region ends up, it rules out R9C4, R10C7 and R10C8. Cross those squares out.
  4. Wherever the cat in the Teal region ends up, it rules out R2C2, R2C4, R2C5, R2C7, R2C8, R2C9 and 2 more. Cross those squares out.
  5. Wherever the cat in the Blue region ends up, it rules out R9C9. Cross that square out.
  6. Wherever the cat in column 8 ends up, it rules out R6C10. Cross that square out.
  7. Wherever the cat in row 6 ends up, it rules out R5C2. Cross that square out.
  8. The Yellow and Blue regions can only use rows 9 and 10, so rows 9 and 10 are already spoken for. Cross out R9C1, R9C2, R9C3, R9C5, R9C8, R10C1 and 1 more.
  9. Wherever the cat in the Grey region ends up, it rules out R8C2, R8C8, R8C9 and R8C10. Cross those squares out.
  10. Wherever the cat in the Green region ends up, it rules out R4C9. Cross that square out.
  11. Wherever the cat in column 2 ends up, it rules out R5C1, R5C3 and R6C1. Cross those squares out.
  12. Wherever the cat in row 6 ends up, it rules out R5C7 and R5C9. Cross those squares out.
  13. Columns 8, 9 and 10 can only use the Green, Blue and Pink regions, so the Green, Blue and Pink regions are already spoken for. Cross out R6C2, R6C3 and R6C4.
  14. Column 2 has only one open square left: R4C2. Put a cat there.
  15. Wherever the cat in the Pink region ends up, it rules out R5C8. Cross that square out.
  16. Row 5 has only one open square left: R5C10. Put a cat there.
  17. The Blue region has only one open square left: R10C9. Put a cat there.
  18. The Yellow region has only one open square left: R9C7. Put a cat there.
  19. The Orange region has only one open square left: R1C5. Put a cat there.
  20. The Pink region has only one open square left: R6C8. Put a cat there.
  21. The Brown region has only one open square left: R3C4. Put a cat there.
  22. The Teal region has only one open square left: R2C1. Put a cat there.
  23. The Grey region has only one open square left: R8C3. 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 18 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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