Complete day 4 part 1

day4/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day4"
+version = "0.1.0"

day4/Cargo.toml

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+[package]
+name = "day4"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

day4/src/main.rs

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+#[derive(Debug, PartialEq, PartialOrd)]
+struct Range {
+    low: u32,
+    high: u32,
+}
+
+impl From<&str> for Range {
+    fn from(s: &str) -> Self {
+        let parts: Vec<&str> = s.split("-").collect();
+
+        let low: u32 = parts[0].parse().unwrap();
+        let high: u32 = parts[1].parse().unwrap();
+
+        Range { low, high }
+    }
+}
+
+impl Range {
+    fn contains(&self, other: &Range) -> bool {
+        self.low <= other.low && self.high >= other.high
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+fn parse_ranges(line: &str) -> (Range, Range) {
+    let ranges: Vec<&str> = line.split(',').collect();
+    let range_a = Range::from(ranges[0]);
+    let range_b = Range::from(ranges[1]);
+
+    (range_a, range_b)
+}
+
+fn main() {
+    let file_str = include_str!("input.txt");
+
+    let count = file_str
+        .lines()
+        .map(|line| parse_ranges(line))
+        .map(|(range_a, range_b)| range_a.contains(&range_b) || range_b.contains(&range_a))
+        .filter(|contains| *contains == true)
+        .collect::<Vec<bool>>()
+        .len();
+
+    println!("Part 1: fully contained pairs: {}", count);
+}