From c54e7dbf8a1624867b0f8bfd2e28fdbd481f4588 Mon Sep 17 00:00:00 2001 From: Santo Cariotti Date: Sun, 10 Dec 2023 11:27:37 +0100 Subject: Add day9 --- 2023/day9/src/lib.rs | 122 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 2023/day9/src/lib.rs (limited to '2023/day9/src') diff --git a/2023/day9/src/lib.rs b/2023/day9/src/lib.rs new file mode 100644 index 0000000..a1b0588 --- /dev/null +++ b/2023/day9/src/lib.rs @@ -0,0 +1,122 @@ +pub fn part1(input: &str) -> i32 { + let mut res: i32 = 0; + + let m: Vec> = input + .trim_end() + .split('\n') + .map(|x| { + x.split(' ') + .map(|y| y.parse::().unwrap()) + .collect::>() + }) + .collect(); + + for i in m { + let mut aux: Vec> = vec![i]; + + let mut z = 1; + loop { + aux.push(vec![]); + for j in 1..aux[z - 1].len() { + let x = aux[z - 1][j] - aux[z - 1][j - 1]; + aux[z].push(x); + } + + if aux[z].iter().filter(|&k| *k != 0).count() == 0 { + aux[z].push(0); + break; + } + + z += 1; + } + + let n = aux.len() - 1; + for j in (0..n).rev() { + let t = aux[j + 1][aux[j + 1].len() - 1]; + let r = aux[j][aux[j].len() - 1]; + aux[j].push(t + r); + } + + res += aux[0][aux[0].len() - 1]; + } + + res +} + +pub fn part2(input: &str) -> i32 { + let mut res: i32 = 0; + + let m: Vec> = input + .trim_end() + .split('\n') + .map(|x| { + x.split(' ') + .map(|y| y.parse::().unwrap()) + .collect::>() + }) + .collect(); + + for i in m { + let mut aux: Vec> = vec![i]; + + let mut z = 1; + loop { + aux.push(vec![]); + for j in 1..aux[z - 1].len() { + let x = aux[z - 1][j] - aux[z - 1][j - 1]; + aux[z].push(x); + } + + if aux[z].iter().filter(|&k| *k != 0).count() == 0 { + aux[z].push(0); + break; + } + + z += 1; + } + + let n = aux.len() - 1; + for j in (0..n).rev() { + let t = aux[j + 1][0]; + let r = aux[j][0]; + aux[j].insert(0, r - t); + } + + res += aux[0][0]; + } + + res +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn example_part1() { + let input = include_str!("../example.txt"); + let result = part1(input); + assert_eq!(result, 114); + } + + #[test] + fn input_part1() { + let input = include_str!("../input.txt"); + let result = part1(input); + assert_eq!(result, 2008960228); + } + + #[test] + fn example_part2() { + let input = include_str!("../example.txt"); + let result = part2(input); + assert_eq!(result, 2); + } + + #[test] + fn input_part2() { + let input = include_str!("../input.txt"); + let result = part2(input); + assert_eq!(result, 71585); + } +} -- cgit v1.2.3-18-g5258