diff --git a/advent_of_code/2024/9/src/main.rs b/advent_of_code/2024/9/src/main.rs
index 1023f6f..e2a36a5 100644
--- a/advent_of_code/2024/9/src/main.rs
+++ b/advent_of_code/2024/9/src/main.rs
@@ -1,8 +1,42 @@
-struct Tree {
+use std::{cell::RefCell, rc::Rc};
 
+#[derive(Debug, Clone)]
+struct FileTree {
+    val: u32,
+    left: Option<TreeNodeRef>,
+    right: Option<TreeNodeRef>,
 }
 
-fn solve_1(input: &str) -> u32 {}
+type TreeNodeRef = Rc<RefCell<FileTree>>;
+
+impl FileTree {
+    fn new() -> Self {
+        FileTree {
+            val: 0,
+            left: None,
+            right: None,
+        }
+    }
+
+    fn fill(&mut self, filesystem: &[u32]) {
+        for (i, file) in filesystem.iter().enumerate() {
+        }
+    }
+
+    fn add_file(&mut self, length: u32) {}
+    fn add_empty(&mut self, length: u32) {}
+}
+
+fn parse(input: &str) -> Vec<u32> {
+    input.chars().map(|c| c.to_digit(10).unwrap()).collect()
+}
+
+fn solve_1(input: &str) -> u32 {
+    let filesystem = parse(input);
+    let mut filetree = FileTree::new();
+
+    filetree.fill(&filesystem[..]);
+}
 
 fn solve_2(input: &str) {}