点つなぎ

Dots and Boxes is a classic pencil-and-paper game where players take turns connecting dots to form squares. The player who completes the fourth side of a square claims it and takes another turn, leading to strategic chain captures.

Complete more squares than your opponent.

Draw a grid of dots (commonly 6x6 or larger). Players choose who goes first. Each player needs a different color pen or uses initials to mark claimed boxes.

1. Players take turns drawing one horizontal or vertical line between two adjacent dots.
2. If a line completes the fourth side of a 1x1 square, that player claims the box (marking it with their initial).
3. Completing a box earns an extra turn - continue playing until you don't complete a box.
4. Multiple boxes can be completed in a single turn if moves chain together.
5. Lines cannot be erased once drawn.
6. Play continues until all boxes are completed.

The player who has claimed more boxes when all are completed wins. Count the boxes marked with each player's initial.

• *In the opening, avoid completing three sides of any box (setting up your opponent).
• *Create 'chains' of three-sided boxes to capture in sequence.
• *When forced to open a chain, give away the shortest chain possible.
• *Learn the 'double-cross' strategy - sacrificing two boxes to gain a longer chain.
• *Count chains and boxes to determine optimal sacrifice points.
• *Control the parity of chains - the player making the last move in a chain often benefits.
• *In the endgame, every move matters - calculate chain lengths carefully.

Dots and Boxes was first published in the 19th century by French mathematician Edouard Lucas. Despite simple rules, optimal play requires complex combinatorial analysis.