46 lines
No EOL
2.1 KiB
Text
46 lines
No EOL
2.1 KiB
Text
\--- Day 1: Not Quite Lisp ---
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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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Your puzzle answer was `232`.
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\--- Part Two ---
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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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Your puzzle answer was `1783`.
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Both parts of this puzzle are complete! They provide two gold stars: \*\*
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At this point, all that is left is for you to [admire your Advent calendar](/2015).
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If you still want to see it, you can [get your puzzle input](1/input). |