Tents and Trees

Tents and Trees is a logic puzzle on a square grid. A tree stands in some of the cells, and a number beside every row and every column says how many tents that line holds; you pitch them so that each tree ends up with a tent of its own directly beside it — above, below, left or right, never across a corner — and no two tents touch, not even at a corner. Nothing is given but the trees and the two strips of numbers, and there are always as many tents as trees. The pairing is the quiet part of it: a tent can stand beside two or three trees and still belong to only one of them, so what the board asks is that the whole wood and the whole camp pair off one to one.

Here a tap crosses a cell out, a second tap pitches a tent on it and a third clears it; drag across cells to cross out several at once. A cross is your own note that no tent goes there, and only the tents are the answer. A tree is drawn as a round crown on a trunk and a tent as an A-frame, told apart by shape alone, and the board tells you only what your own tents already say: a tent reddens when it touches another, when its row or column holds too many, or when no tree stands beside it at all, and a line’s number greys once that line has its tents. No hints, and nothing that checks you against the answer.

A new board every day — 8 × 8, 10 × 10, and 12 × 12 — 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.