Graceful Daily Puzzle

One puzzle a day. The same one for everybody.

Every circle on the board gets a number. Every line takes the difference between the
two circles it joins. You win when no two lines share a value — which means, with ten
lines, the values end up being exactly 1 through 10, each appearing once.

That is the whole rule. It takes thirty seconds to learn and a while to get good at.

A NEW BOARD EVERY DAY
Monday opens easy and the week builds toward the weekend, ending on Sunday's largest
board. Everyone gets the same puzzle on the same day, so you and a friend are solving
the same thing.

TRACK YOUR RUN
Solve the day's puzzle to keep your streak. Share your result as a grid of blocks
that shows the shape of your solve — where you doubled back, where you went straight
through — without giving away a single number.

CATCH UP ALL WEEK
The last seven days are always free. Miss Tuesday, play it Thursday. The full archive
of every earlier puzzle can be unlocked with a single purchase, if you want it. It is
not a subscription, and today's puzzle never needs it.

BUILT TO BE QUIET
No accounts. No ads. No timers pushing you along. Nothing is sent anywhere, and it
all works with no signal at all.

ONE MORE THING
Every board here is a tree, and every tree anyone has ever checked can be labelled
this way. Mathematicians believe they all can. Nobody has proved it. The puzzles you
are solving are small cases of a question that has been open since the 1960s.