37 lines
1.7 KiB
Markdown
37 lines
1.7 KiB
Markdown
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# Day 1: Not Quite Lisp
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## Part 1
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Santa was hoping for a white Christmas, but his weather machine's "snow" function is powered by stars, and he's fresh out! To save Christmas, he needs you to collect fifty stars by December 25th.
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Collect stars by helping Santa solve puzzles. Two puzzles will be made available on each day in the Advent calendar; the second puzzle is unlocked when you complete the first. Each puzzle grants one star. Good luck!
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Here's an easy puzzle to warm you up.
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Santa is trying to deliver presents in a large apartment building, but he can't find the right floor - the directions he got are a little confusing. He starts on the ground floor (floor 0) and then follows the instructions one character at a time.
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An opening parenthesis, (, means he should go up one floor, and a closing parenthesis, ), means he should go down one floor.
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The apartment building is very tall, and the basement is very deep; he will never find the top or bottom floors.
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For example:
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- `(())` and `()()` both result in floor 0.
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- `(((` and `(()(()(` both result in floor 3.
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- `))(((((` also results in floor 3.
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- `())` and `))(` both result in floor -1 (the first basement level).
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- `)))` and `)())())` both result in floor -3.
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**To what floor do the instructions take Santa?**
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## Part 2
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Now, given the same instructions, find the **position** of the first character that causes him to enter the basement (floor -1). The first character in the instructions has position 1, the second character has position 2, and so on.
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For example:
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* `)` causes him to enter the basement at character position 1.
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* `()())` causes him to enter the basement at character position 5.
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What is the position of the character that causes Santa to first enter the basement?
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