[rs] Solve 2022_04 part 1

rs/src/main.rs

@@ -40,6 +40,7 @@ days! {
     Y2022D01: "2022_01",
     Y2022D02: "2022_02",
     Y2022D03: "2022_03",
+    Y2022D04: "2022_04",
 }
 
 #[derive(Parser)]
@@ -75,6 +76,7 @@ fn main() -> io::Result<()> {
             Day::Y2022D01 => y2022::d01::solve(input),
             Day::Y2022D02 => y2022::d02::solve(input),
             Day::Y2022D03 => y2022::d03::solve(input),
+            Day::Y2022D04 => y2022::d04::solve(input),
         }
     }
 

rs/src/y2022.rs

@@ -1,3 +1,4 @@
 pub mod d01;
 pub mod d02;
 pub mod d03;
+pub mod d04;

rs/src/y2022/d04.rs

@@ -0,0 +1,24 @@
+use std::ops::RangeInclusive;
+
+fn contains(a: &RangeInclusive<u32>, b: &RangeInclusive<u32>) -> bool {
+    a.start() <= b.start() && b.end() <= a.end()
+}
+
+pub fn solve(input: String) {
+    let pairs = input
+        .lines()
+        .map(|l| {
+            let mut ranges = l.split(',').map(|p| {
+                let mut numbers = p.split('-').map(|n| n.parse::<u32>().unwrap());
+                numbers.next().unwrap()..=numbers.next().unwrap()
+            });
+            (ranges.next().unwrap(), ranges.next().unwrap())
+        })
+        .collect::<Vec<_>>();
+
+    let score = pairs
+        .iter()
+        .filter(|(a, b)| contains(a, b) || contains(b, a))
+        .count();
+    println!("Part 1: {score}");
+}