Gerrymandering

This week’s Riddler Express challenged us to rig an election!

Imagine your job is to draw districts and you happen to be a member of the Blue Party. The grid below gives the locations of 25 voters in a region, which you must divide into five districts with five voters each. In each district, the party with the most votes will win. The districts must be non-overlapping and contiguous (that is, each square in a district must share an edge with at least one other square in the district). Can you draw the districts such that the Blue Party wins more districts than the Red Party?

Salamander
Salamander this, Gerry

A quick count reveals that there are 9 Blue voters, which happens to be the minimum number of voters needed to win this election. To win an election with 5 District Votes, you need to secure 3 of them. In each of the Districts, the Blue team must win 3 votes. So the task is to distribute the votes in such a way that there are exactly 3 Blue votes in 3 different Districts. This will necessarily mean that the other 2 Districts will be solid Red.

The “contiguous” rule is the main constraint here, and isn’t it weird? It’s like saying, “You’re allowed to cheat. But try to make it look kinda like you’re not cheating.”

Anyways, there wasn’t much math to my method. I just messed around with an Excel spreadsheet with colored cells and thick borders. Here’s what I came up with:

Gerrymander

Everything is a game. Game theory drives the world!

“When you got skin in the game, you stay in the game.
But you don’t get a win unless you’re playing the game.
You get love for it. You get hate for.
You get nothing if you wait for it”

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