48 lines
1.1 KiB
Rust
48 lines
1.1 KiB
Rust
const TEST_INPUT: &str = "\
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3 4
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4 3
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2 5
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1 3
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3 9
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3 3
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";
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const INPUT: &str = include_str!("../inputs/2024/day1.input");
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fn parse(i: &str) -> Vec<(i32, i32)> {
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i
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.lines()
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.map(|l| {
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let ns = l
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.split_once(" ")
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.unwrap();
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(ns.0.parse::<i32>().unwrap(), ns.1.parse::<i32>().unwrap())
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}
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).collect()
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}
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fn the_lists(i: Vec<(i32, i32)>) -> (Vec<i32>, Vec<i32>) {
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let mut left_list: Vec<i32> = vec![];
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let mut right_list: Vec<i32> = vec![];
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for (left, right) in i {
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left_list.push(left);
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right_list.push(right);
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}
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(left_list, right_list)
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}
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pub fn part1() -> i32 {
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let i = parse(INPUT);
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let (mut left_list, mut right_list) = the_lists(i);
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left_list.sort();
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right_list.sort();
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use std::iter::zip;
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zip(left_list.iter(), right_list.iter()).fold(0, |acc, (l, r)| acc + (l - r).abs())
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}
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pub fn part2() -> i32 {
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let i = parse(INPUT);
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let (mut left_list, mut right_list) = the_lists(i);
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left_list.iter().fold(0, |acc, n1|
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acc + n1 * right_list.iter().filter(|n2| n1 == *n2).count() as i32)
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}
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