Gerrymandering, the practice of redrawing political district boundaries to favour a particular party, has a mathematical side. A new puzzle challenges you to draw electoral maps where the minority colour wins the majority of regions.
The puzzles were created by Brady Forrest, a university student in Toronto known online as Deckard. In each grid, you must divide the cells into contiguous regions (connected horizontally or vertically) so that the minority colour wins the most regions. Winning a region means having the most cells of that colour within it.
For example, one puzzle asks you to divide a grid into three regions of three cells each, with purple as the minority colour winning the majority. Another requires five regions of five cells each, again with purple winning. More complex versions involve five regions of ten cells each, and seven regions of seven cells each, with no ties allowed.
Interactive versions of the puzzles are available online, along with printable copies. The puzzles highlight the mathematical intrigue behind gerrymandering, separate from its political implications.
