How to solve PandaPuzz

PandaPuzz is a color-region logic puzzle. Place one panda in every row, every column and every color area, and never let two pandas touch, not even diagonally.

Every puzzle has exactly one solution, and you can always reach it by deduction. Guessing is never needed. This guide solves one small 5x5 puzzle with three simple ideas.

The three rules

One panda in every color area.
One panda in every row and every column.
Pandas never touch, not even diagonally.

1. Start with the smallest area

Look for a color area that is only one cell big. The panda must go there, because the area needs exactly one. In this puzzle the yellow area is a single cell, at row 1, column 3. It is outlined on the board.

The yellow area is one cell, so it holds a panda.

2. Cross out everything a panda touches

A placed panda rules out its whole row, its whole column and the eight cells around it. It also rules out the rest of its own color area. Cross all of these out with an X (tap the cell once in the app).

The X cells are your helpers. Every cross-out shrinks the choices for the other areas.

After the first panda, the cells it rules out are crossed with an X.

3. Find an area stuck in one line

Now look at the purple area. Only two cells are left for it, and both are in column 5: rows 2 and 3. So the purple panda will be in column 5, whichever of the two it is. No other area can use this column.

That means the other cells of column 5 can be crossed out: rows 4 and 5 (the red X marks).

The purple area is stuck in column 5, so the red cells are ruled out.

4. Repeat until it is solved

After each cross-out, look again. A new single cell, a row or column with only one free cell, or another area stuck in a line will appear. Keep going and the puzzle falls apart one step at a time.

A stronger version of the same idea: if two areas live only in the same two rows, those two rows belong to them, so every other cell in those rows can be crossed out. The same works for columns, and for three areas sharing three lines.

The finished puzzle: one panda in every row, column and color area, and none touching.

Tips

Never guess. If no cell is forced, look for another clue: a single cell, a stuck area, or a row or column with one free cell.
Use X marks freely. They cost nothing and make the next clue easier to see.
Count each color, row and column. Every one needs exactly one panda.
Remember the shy rule: pandas cannot touch, even diagonally. The diagonal is easy to miss.
Stuck? Ask for a hint. It explains why a cell is forced, using the same ideas as this guide.
Turn on pattern mode if the colors are hard to tell apart.

Try these ideas in PandaPuzz. The app is coming soon to Google Play. Back to PandaPuzz