diff --git a/src/day07.rs b/src/day07.rs
index 584d914..036b291 100644
--- a/src/day07.rs
+++ b/src/day07.rs
@@ -121,16 +121,11 @@ fn compute_dir_sizes(input: &[CliOperation]) -> Tree<(usize, usize)> {
 #[aoc(day7, part1)]
 fn solve_part1(input: &[CliOperation]) -> usize {
     let tree = compute_dir_sizes(input);
-    let mut sum = 0;
-    for node in tree
-        .traverse_post_order(tree.root_node_id().unwrap())
+    tree.traverse_post_order(tree.root_node_id().unwrap())
         .unwrap()
-    {
-        if node.data().1 <= 100000 {
-            sum += node.data().1;
-        }
-    }
-    sum
+        .map(|node| node.data().1)
+        .filter(|&size| size <= 100_000)
+        .sum()
 }
 
 #[aoc(day7, part2)]