Spring Challenge 2023 - ant pathfinding does not work

In this contest, the only way the players can interact with the game is by moving the ants using the beacons. However, this means that we have to rely on the pathfinding in the referee, which is far from optimal.

For example, you can look at this replay: Coding Games and Programming Challenges to Code Better
The ants take 3 turns to get to the beacons on frames 3-5, even though it’s possible in a single turn.

Moving ants in a straight line in order to create a chain is also not as trivial as one would expect: Coding Games and Programming Challenges to Code Better

… and it gets much, much worse with more beacons/ants - to the point where I expect that placing beacons in a way that avoids the referee bugs will be far more important for a good ranking than e.g. choosing a search algorithm.

TLDR: the pathfinding in “AntAllocater.java” is [insert a non-bannable expletive], which makes it impossible to reliably interact with the game.

19 Likes

Is it too late to add a MOVE command ? That wouldn’t break any bot and allow us to move ants in a precise way.

11 Likes

For the first example, I think the ants took 3 turns because both beacons had a weight of 1, therefore the referee tried to balance the number of ants on each cell (30 each), which is why the ant didn’t move to the closer beacon

There is a simple way to balance the ants between the beacons in just 1 turn (send 10 ants from the base to each of the 2 beacons) and the referee didn’t find it.

2 Likes

Ah I see, I only looked from frame 3 onwards so I missed that move on frame 2->3