From 3cab145b01e41dee6ad5f525655e2b0aa432933f Mon Sep 17 00:00:00 2001
From: Johannes <freelon@gmx.net>
Date: Wed, 11 Dec 2024 20:03:06 +0100
Subject: [PATCH] day 11

---
 newday.sh    |  1 +
 src/day11.rs | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/lib.rs   |  1 +
 src/main.rs  |  1 +
 4 files changed, 68 insertions(+)
 create mode 100644 src/day11.rs

diff --git a/newday.sh b/newday.sh
index 865f693..3a91ee5 100755
--- a/newday.sh
+++ b/newday.sh
@@ -16,6 +16,7 @@ if ! [[ "$X" =~ ^[0-9]{2}$ ]]; then
 fi
 
 cp src/template.rs src/day$X.rs
+git add src/day$X.rs
 touch input/day$X.txt
 
 # Define the placeholder you want to replace
diff --git a/src/day11.rs b/src/day11.rs
new file mode 100644
index 0000000..b9fb10d
--- /dev/null
+++ b/src/day11.rs
@@ -0,0 +1,65 @@
+use std::{collections::HashMap, fs::read_to_string};
+
+pub fn day_main() {
+    let input = read_to_string("input/day11.txt").unwrap();
+    let input = input.trim();
+    println!(" part1: {}", part1(input));
+    println!(" part2: {}", part2(input));
+}
+
+type RiddleResult = usize;
+
+fn part1(input: &str) -> RiddleResult {
+    solve(input, 25)
+}
+
+fn solve(input: &str, blinks: i32) -> usize {
+    let mut stones: HashMap<String, usize> = input.split(" ").map(|v| (v.to_string(), 1)).collect();
+    let mut next = HashMap::new();
+    for _ in 0..blinks {
+        for (k, v) in stones {
+            if k.as_str() == "0" {
+                next.entry("1".to_string())
+                    .and_modify(|count| *count += v)
+                    .or_insert(v);
+            } else if k.len() % 2 == 0 {
+                let (a, b) = k.split_at(k.len() / 2);
+                next.entry(a.to_string())
+                    .and_modify(|count| *count += v)
+                    .or_insert(v);
+                let x = b.parse::<usize>().unwrap().to_string();
+                next.entry(x).and_modify(|count| *count += v).or_insert(v);
+            } else {
+                let d: usize = k.parse().unwrap();
+                let k_new = d * 2024;
+                next.entry(k_new.to_string())
+                    .and_modify(|count| *count += v)
+                    .or_insert(v);
+            }
+        }
+        stones = next;
+        next = HashMap::new();
+    }
+    stones.values().to_owned().sum()
+}
+
+fn part2(input: &str) -> RiddleResult {
+    solve(input, 75)
+}
+
+#[cfg(test)]
+mod test {
+    use super::{part1, part2};
+
+    const TEST_INPUT: &str = r"";
+
+    #[test]
+    fn test1() {
+        assert_eq!(part1("125 17"), 55312);
+    }
+
+    #[test]
+    fn test2() {
+        assert_eq!(part2(TEST_INPUT), 0);
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index ff40f6f..cb167e1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -8,5 +8,6 @@ pub mod day07;
 pub mod day08;
 pub mod day09;
 pub mod day10;
+pub mod day11;
 // PLACEHOLDER
 pub mod utils;
diff --git a/src/main.rs b/src/main.rs
index f28af20..6a4cda3 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -15,6 +15,7 @@ fn main() {
         (8, day08::day_main),
         (9, day09::day_main),
         (10, day10::day_main),
+        (11, day11::day_main),
         // PLACEHOLDER
     ]);
     let day: Option<u8> = args().nth(1).and_then(|a| a.parse().ok());