diff --git a/2022/day04-part1/src/main.rs b/2022/day04-part1/src/main.rs
index bd3b249..4019a26 100644
--- a/2022/day04-part1/src/main.rs
+++ b/2022/day04-part1/src/main.rs
@@ -19,20 +19,28 @@ fn main() {
         // Turn "1-2,3-6" into ["1-2", "3-6"].
         let ranges = line.split(',').collect::<Vec<_>>();
         // Turn ["1-2", "3-6"] into [["1", "2"], ["3", "6"]]
-        let ranges = ranges.iter().map(|x| x.split('-').collect::<Vec<_>>()).collect::<Vec<_>>();
+        let ranges = ranges
+            .iter()
+            .map(|x| x.split('-').collect::<Vec<_>>())
+            .collect::<Vec<_>>();
         // Turn [["1", "2"], ["3", "6"]] into [1..=2, 3..=6]
-        let ranges = ranges.iter().map(|x| (x[0].parse::<i32>().unwrap())..=(x[1].parse::<i32>().unwrap())).collect::<Vec<_>>();
+        let ranges = ranges
+            .iter()
+            .map(|x| (x[0].parse::<i32>().unwrap())..=(x[1].parse::<i32>().unwrap()))
+            .collect::<Vec<_>>();
         // Now turn the ranges into HashSets containing the respective integers. Essentially:
         // Turn [1..=2, 3..=6] into [{1,2}, {3,4,5,6}]
-        let sets = ranges.into_iter().map(|x| x.collect::<HashSet<_>>()).collect::<Vec<_>>();
+        let sets = ranges
+            .into_iter()
+            .map(|x| x.collect::<HashSet<_>>())
+            .collect::<Vec<_>>();
 
+        // Check if either of the sets is a subset of the other, i.e. is fully contained in the other.
+        // If so, add it to the count.
         if sets[0].is_subset(&sets[1]) || sets[1].is_subset(&sets[0]) {
             count += 1;
         }
-
-
     }
 
     println!("Count: {}", count);
 }
-