day 4 part 2

four.rs

@@ -1,6 +1,7 @@
 fn main() {
     let buf = std::fs::read_to_string("four.txt").unwrap();
-    let mut count = 0u32;
+    let mut count_contains = 0u32;
+    let mut count_overlaps = 0u32;
     for line in buf.lines() {
         let (first, last) = line.split_once(',').unwrap();
         let (first_lower, first_upper) = first
@@ -15,13 +16,24 @@ fn main() {
         if contains(first_lower, first_upper, last_lower, last_upper)
             || contains(last_lower, last_upper, first_lower, first_upper)
         {
-            count += 1;
+            count_contains += 1;
+        }
+
+        if overlaps(first_lower, first_upper, last_lower, last_upper)
+            || overlaps(last_lower, last_upper, first_lower, first_upper)
+        {
+            count_overlaps += 1;
         }
     }
 
-    println!("{}", count);
+    println!("{}", count_contains);
+    println!("{}", count_overlaps);
 }
 
 fn contains(a: u32, b: u32, c: u32, d: u32) -> bool {
     return (a..=b).contains(&c) && (a..=b).contains(&d);
 }
+
+fn overlaps(a: u32, b: u32, c: u32, d: u32) -> bool {
+    return (a..=b).contains(&c) || (a..=b).contains(&d);
+}