Futoshiki
Each digit once in every row and column, and the signs between the cells point at the smaller of two.
Futoshiki is a number puzzle on a small square grid. Every row and every column holds the digits from 1 up to the number of its cells, each one once — and between some of the cells stands a sign, pointing at the smaller of the two digits beside it. A board comes with only a few digits: the signs carry the rest, and one chain of them can settle a whole line.
Here it is written the way Sudoku is — pick a cell, pick a digit, pencil in notes if you like — and the board tells you only what the digits standing on it already say: a digit its row or column already holds turns reddish, and so does a digit on the wrong side of a sign, with that sign. No hints, and nothing that checks you against the answer. The puzzle is Japanese for “inequality”, and goes by More or Less in English and by the spelling hutosiki as well.
A new board every day — 5 × 5, 6 × 6, and 7 × 7 — the same for everybody, each with a single solution that reasoning alone reaches. No timer and no account needed: a board left half-done waits for you until the day turns, at midnight UTC.
Today’s boards
How to play
Every row and every column holds the digits from 1 up to the number of its cells, each one once — on a 5 × 5 that is 1 to 5.
A sign between two cells points at the smaller of the two digits: 2 < 5, and 5 > 2. Between a cell and the one below it, it reads the same way.
A few digits come with the board; the signs carry the rest.
Tap a cell and pick a digit on the pad under the board; the same digit again clears it. With notes on, digits are pencilled small in the cell instead. The digits the board came with stay put, and the signs take no taps — a tap on one lands on the cell under your finger.
A reddish cell holds a digit its row or column already has, or a digit on the wrong side of a sign — and that sign reddens with it.
Beyond today’s board
No timer. Leave and come back — it’s saved.
Play today’s Futoshiki