feat: completed part 1

ankjevel · ankjevel · commit bada40def9ee · 2023-12-04T11:33:37.000+01:00
diff --git a/README.md b/README.md
@@ -5,7 +5,7 @@
 - [Day 1](https://github.com/ankjevel/adventofcode/tree/2023/day_01) ⭐️ ⭐️
 - [Day 2](https://github.com/ankjevel/adventofcode/tree/2023/day_02) ⭐️ ⭐️
 - [Day 3](https://github.com/ankjevel/adventofcode/tree/2023/day_03) ⭐️ ⭐️
-- [Day 4](#)
+- [Day 4](https://github.com/ankjevel/adventofcode/tree/2023/day_04) ⭐️
 - [Day 5](#)
 - [Day 6](#)
 - [Day 7](#)
diff --git a/day_04/Cargo.toml b/day_04/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "day_04"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+doctest = false
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/day_04/src/lib.rs b/day_04/src/lib.rs
@@ -0,0 +1,52 @@
+pub mod part_01;
+
+pub type Input = Vec<(Vec<u16>, Vec<u16>)>;
+
+fn numbers(input: &str) -> Vec<u16> {
+    input
+        .split(' ')
+        .filter(|string| !string.trim().is_empty())
+        .map(|string| string.trim().parse::<_>().unwrap())
+        .collect()
+}
+
+pub fn parse_input(input: &str) -> Input {
+    input
+        .trim_start()
+        .trim_end()
+        .lines()
+        .map(str::trim)
+        .map(|string| {
+            let card = string.split(": ").collect::<Vec<_>>()[1];
+            let split = card.split(" | ").collect::<Vec<_>>();
+            (numbers(split[0]), numbers(split[1]))
+        })
+        .collect()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const EXAMPLE_DATA: &'static str = "
+        Card 1: 41 48 83 86 17 | 83 86  6 31 17  9 48 53
+        Card 2: 13 32 20 16 61 | 61 30 68 82 17 32 24 19
+    ";
+
+    #[test]
+    fn it_parses_example() {
+        assert_eq!(
+            parse_input(&EXAMPLE_DATA),
+            vec![
+                (
+                    vec![41, 48, 83, 86, 17], //
+                    vec![83, 86, 6, 31, 17, 9, 48, 53]
+                ),
+                (
+                    vec![13, 32, 20, 16, 61], //
+                    vec![61, 30, 68, 82, 17, 32, 24, 19]
+                )
+            ]
+        );
+    }
+}
diff --git a/day_04/src/main.rs b/day_04/src/main.rs
@@ -0,0 +1,11 @@
+use std::io::Result;
+
+use day_04::{parse_input, part_01::main as part_01};
+
+fn main() -> Result<()> {
+    let input = parse_input(include_str!("../../input/day_04"));
+
+    println!("part_01: {:?}", part_01(&input)?);
+
+    Ok(())
+}
diff --git a/day_04/src/part_01.rs b/day_04/src/part_01.rs
@@ -0,0 +1,37 @@
+use std::io::Result;
+
+use crate::Input;
+
+pub fn main(input: &Input) -> Result<u32> {
+    Ok(input
+        .iter()
+        .map(|(winning_numbers, numbers)| {
+            winning_numbers
+                .iter()
+                .filter(|n| numbers.contains(n))
+                .fold(0, |sum, _| if sum == 0 { 1 } else { sum * 2 })
+        })
+        .sum())
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::parse_input;
+
+    use super::*;
+
+    const EXAMPLE_DATA: &'static str = "
+        Card 1: 41 48 83 86 17 | 83 86  6 31 17  9 48 53
+        Card 2: 13 32 20 16 61 | 61 30 68 82 17 32 24 19
+        Card 3:  1 21 53 59 44 | 69 82 63 72 16 21 14  1
+        Card 4: 41 92 73 84 69 | 59 84 76 51 58  5 54 83
+        Card 5: 87 83 26 28 32 | 88 30 70 12 93 22 82 36
+        Card 6: 31 18 13 56 72 | 74 77 10 23 35 67 36 11
+    ";
+
+    #[test]
+    fn it_gets_the_example_correct() -> Result<()> {
+        assert_eq!(main(&parse_input(&EXAMPLE_DATA))?, 13);
+        Ok(())
+    }
+}
diff --git a/input/day_04 b/input/day_04
