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--- Day 7: The Treachery of Whales ---
A giant whale has decided your submarine is its next meal, and it's much faster than you are.
There's nowhere to run!
Suddenly, a swarm of crabs (each in its own tiny submarine - it's too deep for them otherwise) zooms
in to rescue you! They seem to be preparing to blast a hole in the ocean floor; sensors indicate a
[1m[37mmassive underground cave system[0m just beyond where they're aiming!
The crab submarines all need to be aligned before they'll have enough power to blast a large enough
hole for your submarine to get through. However, it doesn't look like they'll be aligned before the
whale catches you! Maybe you can help?
There's one major catch - crab submarines can only move horizontally.
You quickly make a list of [1m[37mthe horizontal position of each crab[0m (your puzzle input). Crab submarines
have limited fuel, so you need to find a way to make all of their horizontal positions match while
requiring them to spend as little fuel as possible.
For example, consider the following horizontal positions:
16,1,2,0,4,2,7,1,2,14
This means there's a crab with horizontal position 16, a crab with horizontal position 1, and so on.
Each change of 1 step in horizontal position of a single crab costs 1 fuel. You could choose any
horizontal position to align them all on, but the one that costs the least fuel is horizontal
position 2:
- Move from 16 to 2: 14 fuel
- Move from 1 to 2: 1 fuel
- Move from 2 to 2: 0 fuel
- Move from 0 to 2: 2 fuel
- Move from 4 to 2: 2 fuel
- Move from 2 to 2: 0 fuel
- Move from 7 to 2: 5 fuel
- Move from 1 to 2: 1 fuel
- Move from 2 to 2: 0 fuel
- Move from 14 to 2: 12 fuel
This costs a total of [1m[37m37[0m fuel. This is the cheapest possible outcome; more expensive outcomes
include aligning at position 1 (41 fuel), position 3 (39 fuel), or position 10 (71 fuel).
Determine the horizontal position that the crabs can align to using the least fuel possible.
[1m[37mHow much fuel must they spend to align to that position?[0m
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