[rs] Solve 2022_04 part 2

rs/src/y2022/d04.rs

@@ -4,6 +4,10 @@ fn contains(a: &RangeInclusive<u32>, b: &RangeInclusive<u32>) -> bool {
     a.start() <= b.start() && b.end() <= a.end()
 }
 
+fn overlap(a: &RangeInclusive<u32>, b: &RangeInclusive<u32>) -> bool {
+    a.contains(b.start()) || a.contains(b.end()) || b.contains(a.start()) || b.contains(a.end())
+}
+
 pub fn solve(input: String) {
     let pairs = input
         .lines()
@@ -21,4 +25,7 @@ pub fn solve(input: String) {
         .filter(|(a, b)| contains(a, b) || contains(b, a))
         .count();
     println!("Part 1: {score}");
+
+    let score = pairs.iter().filter(|(a, b)| overlap(a, b)).count();
+    println!("Part 2: {score}");
 }