[rs] Simplify 2022_04

rs/src/y2022/d04.rs

@@ -1,31 +1,26 @@
-use std::ops::RangeInclusive;
-
-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()
         .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()
+                (numbers.next().unwrap(), numbers.next().unwrap())
             });
             (ranges.next().unwrap(), ranges.next().unwrap())
         })
         .collect::<Vec<_>>();
 
+    // Part 1
     let score = pairs
         .iter()
-        .filter(|(a, b)| contains(a, b) || contains(b, a))
+        .filter(|((s1, e1), (s2, e2))| (s1 <= s2 && e2 <= e1) || (s2 <= s1 && e1 <= e2))
         .count();
     println!("Part 1: {score}");
 
-    let score = pairs.iter().filter(|(a, b)| overlap(a, b)).count();
+    // Part 2
+    let score = pairs
+        .iter()
+        .filter(|((s1, e1), (s2, e2))| s1 <= e2 && s2 <= e1)
+        .count();
     println!("Part 2: {score}");
 }