diff --git a/2022/rust/Cargo.toml b/2022/rust/Cargo.toml
index e10a2b9..0416b00 100644
--- a/2022/rust/Cargo.toml
+++ b/2022/rust/Cargo.toml
@@ -38,4 +38,8 @@ path = "src/day5.rs"
 name = "day6"
 path = "src/day6.rs"
 
+[[bin]]
+name = "day7"
+path = "src/day7.rs"
+
 [dependencies]
diff --git a/2022/rust/src/day7.rs b/2022/rust/src/day7.rs
new file mode 100644
index 0000000..6244fc7
--- /dev/null
+++ b/2022/rust/src/day7.rs
@@ -0,0 +1,145 @@
+mod common;
+
+use std::cell::RefCell;
+use std::collections::HashMap;
+use std::rc::Rc;
+
+#[derive(Debug, Clone)]
+struct DirTree {
+    files: HashMap<String, usize>,
+    subdirectories: HashMap<String, Rc<RefCell<Self>>>,
+    parent: Option<Rc<RefCell<Self>>>,
+}
+
+impl DirTree {
+    pub fn new(parent: Option<Rc<RefCell<Self>>>) -> Self {
+        Self {
+            files: HashMap::new(),
+            subdirectories: HashMap::new(),
+            parent,
+        }
+    }
+
+    pub fn root() -> Self {
+        Self::new(None)
+    }
+
+    pub fn size(&self) -> usize {
+        self.files.values().sum::<usize>()
+            + self
+                .subdirectories
+                .values()
+                .map(|v| v.borrow().size())
+                .sum::<usize>()
+    }
+}
+
+struct DirTreeIterator {
+    dir_tree: Rc<RefCell<DirTree>>,
+}
+
+impl IntoIterator for DirTree {
+    type Item = Rc<RefCell<DirTree>>;
+    type IntoIter = std::iter::Chain<
+        std::iter::Once<Rc<RefCell<DirTree>>>,
+        std::collections::hash_map::Values<String, Rc<RefCell<DirTree>>>,
+    >;
+
+    fn into_iter(&self) -> Self::IntoIter {
+        std::iter::once(Rc::new(RefCell::new(*self)))
+            .into_iter()
+            .chain(self.subdirectories.values().into_iter())
+    }
+}
+
+type Input = Rc<RefCell<DirTree>>;
+type Result = usize;
+
+fn processed_input(input: &str) -> Input {
+    let root = Rc::new(RefCell::new(DirTree::root()));
+    let mut current_dir = Rc::clone(&root);
+    for l in input.lines() {
+        println!("{}", l);
+        if l == "$ cd /" {
+            current_dir = Rc::clone(&root);
+        } else if l == "$ ls" {
+            continue;
+        } else if l.starts_with("dir ") {
+            current_dir.borrow_mut().subdirectories.insert(
+                l[4..].to_string(),
+                Rc::new(RefCell::new(DirTree::new(Some(Rc::clone(&current_dir))))),
+            );
+        } else if l.starts_with("$ cd ..") {
+            let cur = Rc::clone(&current_dir);
+            current_dir = Rc::clone(&cur.borrow().parent.as_ref().unwrap());
+        } else if l.starts_with("$ cd ") {
+            let cur = Rc::clone(&current_dir);
+            current_dir = Rc::clone(&cur.borrow().subdirectories.get(&l[5..]).unwrap());
+        } else {
+            let mut args = l.split(' ');
+            let size = args.next().unwrap().parse::<usize>().unwrap();
+            current_dir
+                .borrow_mut()
+                .files
+                .insert(args.next().unwrap().to_string(), size);
+        }
+    }
+    return root;
+}
+
+fn part1(input: &Input) -> Result {
+    100
+}
+
+fn part2(input: &Input) -> Result {
+    0
+}
+
+fn main() {
+    let input_text = common::day_input(7);
+    eprintln!("{}\n\nAbove is your input file.\n\n", input_text);
+    let input = processed_input(&input_text);
+    common::show_answers(&part1(&input), &part2(&input))
+    // common::show_both_answers(&both_parts(&input))
+}
+
+// fn both_parts(input: &Input) -> (Result, Result) {
+//     (0, 0)
+// }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const TEST_INPUT: &str = "$ cd /
+$ ls
+dir a
+14848514 b.txt
+8504156 c.dat
+dir d
+$ cd a
+$ ls
+dir e
+29116 f
+2557 g
+62596 h.lst
+$ cd e
+$ ls
+584 i
+$ cd ..
+$ cd ..
+$ cd d
+$ ls
+4060174 j
+8033020 d.log
+5626152 d.ext
+7214296 k";
+
+    #[test]
+    fn test() {
+        let input = processed_input(TEST_INPUT);
+        assert_eq!(part1(&input), 95437);
+        assert_eq!(part2(&input), 0);
+        // assert_eq!(both_parts(&input), (0, 0));
+    }
+}