28 lines
1.3 KiB
Markdown
28 lines
1.3 KiB
Markdown
# Day1: Not Quite Lisp
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## Part 1
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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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