Sprouts is an interesting paper and pencil game for two players. It was invented in
Cambridge in the
1970's.
To begin, mark five large dots on a piece of paper. The two players take turns to draw a line joining two of the dots together, subject to the following restrictions.
- The line must not cross itself or any other line.
- No dot may have more than three lines joined to it.
The player then makes a new dot at any position along this line, and play then passes to the opponent. This process is repeated until one player cannot draw a valid line: this player is the loser.
Sprouts is an interesting problem in
topology. At the start of the game three lines can be drawn to each of the points, so there are fifteen open 'connections'. On each turn, two connections are removed, and an extra one created, hence the maximum number of turns will be fourteen. The
strategy to Sprouts comes from
isolating the connections from one another, to reduce the total number of valid moves. Experienced players may use more than five dots to begin with.