How to play Ripple Rooms

Fill each room with 1 to its size so that any two equal numbers in the same row or column have at least that many squares between them. Also known as Ripple puzzle, Room distance numbers.

▶ Play Ripple Rooms ⊞ Open the solver

The rules

The grid is divided into rooms outlined in bold.
A room of n squares contains each number from 1 to n once.
If the same number N appears twice in a row or column, there must be at least N squares between them.
Given numbers can’t be changed.

Playing Ripple Rooms on Puzzle Solvers

Choose a size, the biggest room and a difficulty, then press New Puzzle.
Tap a square, then a number on the pad (or type it). Use Notes (N, or Shift + number) for pencil marks.
Select a number to see its ripple — the squares along its row and column where that number can’t go.
Hint explains the next number: single squares, the only place left in a room, and ripples that reach whichever square a number picks.

Open the Ripple Rooms game →

Using the Ripple Rooms solver

Choose the size, draw the rooms (or press Sample), then type the given numbers.
Press Solve and step through each number with its ripple shown.

Open the solver →

A worked example

A two-square room sits in a row next to a one-square room. The single room is 1, so the neighbouring square of the two-room can’t be 1 — it’s 2, and the other square is 1.

That 2 ripples two squares each way along its row and column, ruling out 2 there.

Strategies

Single rooms. A one-square room holds 1, so the squares directly beside it in its row and column can’t be 1.
Big ripples. A 5 rules out 5s for five squares in every direction — place large numbers first.
Only place. If a room’s 3 can only fit in one square, it goes there.
Every ripple. If a room’s number must go in one of two squares, a square that both ripples reach can’t be that number.
Edges help. Near the edge, ripples have less room to spread, so numbers are often forced there.

Common mistakes

Measuring the distance wrongly — two 3s need three squares in between, not three squares apart.
Applying the ripple diagonally — it only runs along rows and columns.
Putting a number bigger than the room’s size.

Where it comes from

Room-and-distance puzzles like this were first published by the Japanese puzzle company Nikoli and are a favourite of number-logic fans.

Frequently asked questions

Does the ripple pass through room walls?

Yes — it runs along the whole row and column, across any rooms.

Is there always one answer?

Yes — every puzzle here is checked to have exactly one solution.

What is the ripple display?

When you select a placed number, the squares its ripple reaches are circled.

How do I solve one from a book?

Open the Ripple Rooms Solver, draw the rooms, type the givens and press Solve.

Keep going

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