32 lines
1.3 KiB
Markdown
32 lines
1.3 KiB
Markdown
# 2020 Day 1: Report Repair
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Copyright (c) Eric Wastl
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#### [Direct Link](https://adventofcode.com/2020/day/1)
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## Part 1
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Before you leave, the Elves in accounting just need you to fix your **expense report** (your puzzle input); apparently, something isn't quite adding up.
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Specifically, they need you to **find the two entries that sum to `2020`** and then multiply those two numbers together.
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For example, suppose your expense report contained the following:
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```
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1721
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979
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366
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299
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675
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1456
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```
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In this list, the two entries that sum to `2020` are `1721` and `299`. Multiplying them together produces `1721 * 299 = 514579`, so the correct answer is **`514579`**.
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Of course, your expense report is much larger. **Find the two entries that sum to `2020`; what do you get if you multiply them together?**
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## Part 2
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The Elves in accounting are thankful for your help; one of them even offers you a starfish coin they had left over from a past vacation. They offer you a second one if you can find **three** numbers in your expense report that meet the same criteria.
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Using the above example again, the three entries that sum to `2020` are `979`, `366`, and `675`. Multiplying them together produces the answer, **`241861950`**.
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In your expense report, **what is the product of the three entries that sum to `2020`**? |