Bug-out Shelter #5 – Outpost Surveillance

Mission

As you secure the silence inside, Maxime sends you a batch of readings retrieved from the abandoned sensor network surrounding the military station. The data is incomplete, noisy, and sampled at irregular intervals — but it’s your only window into what the raiders are up to.

Your mission is simple and urgent: analyze these coordinates to determine the general direction and proximity of the threat relative to the station, and assess whether their trajectory is converging toward Promèthes. This estimation will immediately inform defensive priorities.

Rules

You are in a two-dimensional space, y and x. The values are expressed in kilometers.

You receive coordinates in the form of a grid composed of 5 lines.

Each line contains the following information:

• A Y coordinate
• A set of X coordinates representing several shelters

Finally, you are given x and y, which are the coordinates of the military base.

You must find the shelters that are within a radius of 20 km or less from the military base, and return the number of shelters found and the X coordinates of the shelters located near the base, in the following format (without the braces):

{nb_shelters}:{shelter1_x},{shelter2_x},{shelter3_x}

Example:

5:22,7,18,36,29