Day 4, puzzle 1

src/bin/d4p1.rs

@@ -0,0 +1,12 @@
+use aoc22::{day4, util};
+
+pub fn main() {
+    let assignments = day4::parse_assignments(&util::parse_input());
+
+    let overlapping = assignments
+        .iter()
+        .filter(|a| a.0.contains(&a.1) || a.1.contains(&a.0))
+        .count();
+
+    println!("{} assignments overlap", overlapping);
+}