Advent of Code F# – Day 17

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The source code for this post (both Part 1 and Part 2) is available here and you can click here to see my solutions for the other Advent of Code challenges.

Description for today’s challenge is here.

 

Another nice and simple challenge whose solution fits nicely into 20 lines, so here goes:

day17_01

If you have been following this series of posts on this blog, then you’ll have seen something similar to this code in previous challenges already. Couple of subtle points to note here:

  • we only yield a combination if the total volume of the containers matches the total (could have done the filtering after the fact, AFAIK there’s no significant performance difference in both approaches);
  • we’re using a depth-first approach here – yield the combinations without the current container first, then only yield combinations with this container if it wouldn’t take us over the 150 litre limit

 

Part 2

The combination-finding code stays the same, we just need to filter the combos after the fact by length:

day17_02

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