diff options
Diffstat (limited to '2024/11/rust')
| -rw-r--r-- | 2024/11/rust/Cargo.lock | 7 | ||||
| -rw-r--r-- | 2024/11/rust/Cargo.toml | 6 | ||||
| -rw-r--r-- | 2024/11/rust/src/main.rs | 43 |
3 files changed, 0 insertions, 56 deletions
diff --git a/2024/11/rust/Cargo.lock b/2024/11/rust/Cargo.lock deleted file mode 100644 index 22c9989..0000000 --- a/2024/11/rust/Cargo.lock +++ /dev/null @@ -1,7 +0,0 @@ -# This file is automatically @generated by Cargo. -# It is not intended for manual editing. -version = 4 - -[[package]] -name = "aoc_2024-11" -version = "0.1.0" diff --git a/2024/11/rust/Cargo.toml b/2024/11/rust/Cargo.toml deleted file mode 100644 index 67185f7..0000000 --- a/2024/11/rust/Cargo.toml +++ /dev/null @@ -1,6 +0,0 @@ -[package] -name = "aoc_2024-11" -version = "0.1.0" -edition = "2021" - -[dependencies] diff --git a/2024/11/rust/src/main.rs b/2024/11/rust/src/main.rs deleted file mode 100644 index e352ec4..0000000 --- a/2024/11/rust/src/main.rs +++ /dev/null @@ -1,43 +0,0 @@ -use std::{collections::HashMap, io}; - -fn blink(k @ (s, n): (u64, u64), cache: &mut HashMap<(u64, u64), u64>) -> u64 { - if n == 0 { - return 1; - } - if let Some(v) = cache.get(&k) { - return *v; - } - - // cache this - let v = { - if s == 0 { - return blink((1, n - 1), cache); - } - let digits = s.ilog10() + 1; - let mid = 10u64.pow(digits / 2); - if digits % 2 == 0 { - blink((s / mid, n - 1), cache) + blink((s % mid, n - 1), cache) - } else { - blink((s * 2024, n - 1), cache) - } - }; - - *cache.entry(k).or_insert(v) -} - -fn main() -> io::Result<()> { - let line = io::stdin().lines().flatten().next().unwrap(); - let stones = line - .split_whitespace() - .map(|s| s.parse::<u64>().unwrap()) - .collect::<Vec<_>>(); - - let mut cache = HashMap::new(); - let silver: u64 = stones.iter().map(|s| blink((*s, 25), &mut cache)).sum(); - let gold: u64 = stones.iter().map(|s| blink((*s, 75), &mut cache)).sum(); - - println!("silver: {silver}"); - println!("gold: {gold}"); - - return Ok(()); -} |
