# Day 5: Cafeteria

[https://adventofcode.com/2025/day/5](https://adventofcode.com/2025/day/5)

## Description

### Part One

As the forklifts break through the wall, the Elves are delighted to discover that there was a cafeteria on the other side after all.

You can hear a commotion coming from the kitchen. "At this rate, we won't have any time left to put the wreaths up in the dining hall!" Resolute in your quest, you investigate.

"If only we hadn't switched to the new inventory management system right before Christmas!" another Elf exclaims. You ask what's going on.

The Elves in the kitchen explain the situation: because of their complicated new inventory management system, they can't figure out which of their ingredients are _fresh_ and which are <span title="No, this puzzle does not take place on Gleba. Why do you ask?"><em>spoiled</em></span>. When you ask how it works, they give you a copy of their database (your puzzle input).

The database operates on _ingredient IDs_. It consists of a list of _fresh ingredient ID ranges_, a blank line, and a list of _available ingredient IDs_. For example:

    3-5
    10-14
    16-20
    12-18
    
    1
    5
    8
    11
    17
    32
    

The fresh ID ranges are _inclusive_: the range `3-5` means that ingredient IDs `3`, `4`, and `5` are all _fresh_. The ranges can also _overlap_; an ingredient ID is fresh if it is in _any_ range.

The Elves are trying to determine which of the _available ingredient IDs_ are _fresh_. In this example, this is done as follows:

*   Ingredient ID `1` is spoiled because it does not fall into any range.
*   Ingredient ID `5` is _fresh_ because it falls into range `3-5`.
*   Ingredient ID `8` is spoiled.
*   Ingredient ID `11` is _fresh_ because it falls into range `10-14`.
*   Ingredient ID `17` is _fresh_ because it falls into range `16-20` as well as range `12-18`.
*   Ingredient ID `32` is spoiled.

So, in this example, _`3`_ of the available ingredient IDs are fresh.

Process the database file from the new inventory management system. _How many of the available ingredient IDs are fresh?_

### Part Two

The Elves start bringing their spoiled inventory to the trash chute at the back of the kitchen.

So that they can stop bugging you when they get new inventory, the Elves would like to know _all_ of the IDs that the _fresh ingredient ID ranges_ consider to be _fresh_. An ingredient ID is still considered fresh if it is in any range.

Now, the second section of the database (the available ingredient IDs) is irrelevant. Here are the fresh ingredient ID ranges from the above example:

    3-5
    10-14
    16-20
    12-18
    

The ingredient IDs that these ranges consider to be fresh are `3`, `4`, `5`, `10`, `11`, `12`, `13`, `14`, `15`, `16`, `17`, `18`, `19`, and `20`. So, in this example, the fresh ingredient ID ranges consider a total of _`14`_ ingredient IDs to be fresh.

Process the database file again. _How many ingredient IDs are considered to be fresh according to the fresh ingredient ID ranges?_