diff --git a/src/main.rs b/src/main.rs
index 697cdec..8c700eb 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,6 +1,8 @@
-use advent_of_code::{prob1, prob2, prob3, prob4, prob5, prob6};
+use advent_of_code::{prob1, prob2, prob3, prob4, prob5, prob6, prob7};
+use color_eyre::eyre::Result;
 
-fn main() {
+fn main() -> Result<()> {
+    color_eyre::install()?;
     {
         let file_path = "prob1.txt";
         let max_part1 = prob1::solve_part1(file_path);
@@ -53,4 +55,10 @@ fn main() {
         let solution = prob6::solve_part2(include_str!("../prob6_part1.txt"));
         println!("Solution for problem 6 part 2: {solution}");
     }
+    {
+        let _file_path = "prob7.txt";
+        let solution = prob7::solve_part1(include_str!("../prob7.txt"))?;
+        println!("Solution for problem 7 part 1: {solution}");
+    }
+    Ok(())
 }
diff --git a/src/prob7.rs b/src/prob7.rs
index c55f7e0..6cf4dac 100644
--- a/src/prob7.rs
+++ b/src/prob7.rs
@@ -1,11 +1,9 @@
-use std::collections::HashMap;
-
 use camino::Utf8PathBuf;
-use nom::combinator::all_consuming;
+use id_tree::{InsertBehavior, Node, Tree};
 use nom::{
     branch::alt,
     bytes::complete::{tag, take_while1},
-    combinator::map,
+    combinator::{all_consuming, map},
     sequence::{preceded, separated_pair},
     Finish, IResult,
 };
@@ -46,9 +44,10 @@ impl From<Cd> for Command {
     }
 }
 
-struct Node {
-    children: HashMap<String, Node>,
-    size: u32,
+#[derive(Debug, Default)]
+struct FsEntry {
+    path: Utf8PathBuf,
+    size: u64,
 }
 
 fn parse_entry(input: &str) -> IResult<&str, Entry> {
@@ -87,7 +86,15 @@ fn parse_line(input: &str) -> IResult<&str, Line> {
     ))(input)
 }
 
-pub fn solve_part1(content: &str) {
+fn total_size(tree: &Tree<FsEntry>, node: &Node<FsEntry>) -> color_eyre::Result<u64> {
+    let mut total = node.data().size;
+    for child in node.children() {
+        total += total_size(tree, tree.get(child)?)?;
+    }
+    Ok(total)
+}
+
+fn generate_tree(content: &str) -> color_eyre::Result<Tree<FsEntry>> {
     let lines = content.lines().map(|line| {
         all_consuming(parse_line)(line)
             .finish()
@@ -95,7 +102,58 @@ pub fn solve_part1(content: &str) {
             .1
     });
 
+    let mut tree = Tree::<FsEntry>::new();
+    let root = tree.insert(
+        Node::new(FsEntry {
+            path: "/".into(),
+            size: 0,
+        }),
+        InsertBehavior::AsRoot,
+    )?;
+    let mut curr = root;
+
     for line in lines {
         println!("{line:?}");
+        match line {
+            Line::Command(cmd) => match cmd {
+                Command::Ls => {}
+                Command::Cd(path) => match path.as_str() {
+                    "/" => {}
+                    ".." => {
+                        curr = tree.get(&curr)?.parent().unwrap().clone();
+                    }
+                    _ => {
+                        curr = tree.insert(
+                            Node::new(FsEntry {
+                                path: path.clone(),
+                                size: 0,
+                            }),
+                            InsertBehavior::UnderNode(&curr),
+                        )?;
+                    }
+                },
+            },
+            Line::Entry(entry) => match entry {
+                Entry::Dir(_) => {}
+                Entry::File(size, name) => {
+                    curr = tree.insert(
+                        Node::new(FsEntry { path: name, size }),
+                        InsertBehavior::UnderNode(&curr),
+                    )?;
+                }
+            },
+        }
     }
+    Ok(tree)
+}
+
+pub fn solve_part1(content: &str) -> color_eyre::Result<u64> {
+    let tree = generate_tree(content)?;
+    let sum = tree
+        .traverse_pre_order(tree.root_node_id().unwrap())?
+        .filter(|n| !n.children().is_empty())
+        .map(|n| total_size(&tree, n).unwrap())
+        .filter(|&s| s <= 100_000)
+        .sum::<u64>();
+    Ok(sum)
 }