Find the Cat #250: 10x10 Grid Puzzle (Hard)

hard

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

0 / 10 cats · 0:00
Red (10)Orange (6)Yellow (7)Green (8)Teal (11)Blue (13)Purple (17)Pink (1)Brown (10)Grey (17)

A 10x10 logic grid, 10 colors, 10 cats. Work out where each cat sits using nothing but the rules -- there is only one correct layout and no guessing is needed.

  • 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 Pink region has only one open square left: R5C6. Put a cat there.
  2. Wherever the cat in the Orange region ends up, it rules out R2C2. Cross that square out.
  3. Wherever the cat in the Green region ends up, it rules out R2C4. Cross that square out.
  4. Wherever the cat in the Brown region ends up, it rules out R2C8, R3C8 and R7C7. Cross those squares out.
  5. Wherever the cat in the Yellow region ends up, it rules out R1C10. Cross that square out.
  6. The Red, Orange, Yellow and Green regions can only use rows 1, 2, 3 and 4, so rows 1, 2, 3 and 4 are already spoken for. Cross out R2C7, R2C10, R3C7, R3C9, R3C10, R4C1 and 4 more.
  7. The Brown region has only one open square left: R6C8. Put a cat there.
  8. The Purple region has only one open square left: R8C9. Put a cat there.
  9. The Yellow region has only one open square left: R1C7. Put a cat there.
  10. Column 10 has only one open square left: R10C10. Put a cat there.
  11. Wherever the cat in the Orange region ends up, it rules out R3C2. Cross that square out.
  12. Wherever the cat in the Red region ends up, it rules out R4C4. Cross that square out.
  13. The Green region has only one open square left: R2C5. Put a cat there.
  14. The Orange region has only one open square left: R3C1. Put a cat there.
  15. The Red region has only one open square left: R4C3. Put a cat there.
  16. The Teal region has only one open square left: R9C4. Put a cat there.
  17. The Grey region has only one open square left: R7C2. Put a cat there.

About this puzzle

Where to start: the Pink region is a single square, so its cat is already decided. Its 10 color regions range from 1 square (Pink) to 17 squares. It can be solved in 17 deduction steps using grouped row/column/region deductions.

Start with the region that is a single square -- its cat has nowhere else to go. Cross out that cat's whole row, column and neighbors, then move on to the next-smallest regions: with only a couple of squares each, they leave very little room.

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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