40 lines
772 B
Rust
40 lines
772 B
Rust
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use crate::prelude::*;
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pub fn solution() -> Solution {
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Solution::new(Day::new(1, 2020), part_1, part_2)
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.with_expected(605364, 128397680)
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}
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const TARGET: i32 = 2020;
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fn parse_lines(input: &str) -> Vec<i32> {
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input
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.lines()
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.filter_map(|line| line.parse::<i32>().ok())
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.collect()
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}
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fn part_1(input: &str) -> Result<String> {
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Ok(
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parse_lines(input)
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.into_iter()
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.tuple_combinations()
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.find(|(a, b)| a + b == TARGET)
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.map(|(a, b)| a * b)
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.unwrap()
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.to_string(),
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)
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}
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fn part_2(input: &str) -> Result<String> {
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Ok(
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parse_lines(input)
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.into_iter()
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.tuple_combinations()
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.find(|(a, b, c)| a + b + c == TARGET)
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.map(|(a, b, c)| a * b * c)
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.unwrap()
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.to_string(),
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)
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}
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