Next star gotten

src/bin/p07.rs

@@ -301,4 +301,34 @@ fn part1(lines: &[String]) {
         .sum::<usize>());
 }
 
-fn part2(_lines: &[String]) {}
+fn part2(lines: &[String]) {
+    let mut state = State::new();
+
+    lines
+        .iter()
+        .flat_map(|l| line(l))
+        .for_each(|(_, l)| state.process(l).unwrap());
+
+    let full_size = state.filesystem.calculate_size();
+    dbg!(full_size);
+
+    const AVAILABLE_SPACE: usize = 70_000_000;
+    const DESIRED_AVAILABLE_SPACE: usize = 30_000_000;
+    const MAX_USED: usize = AVAILABLE_SPACE - DESIRED_AVAILABLE_SPACE;
+
+    let over_by = full_size - MAX_USED;
+
+    println!(
+        "{}",
+        state
+            .filesystem
+            .into_iter()
+            .filter(|f| f.is_dir()
+                && match f.size {
+                    Some(s) => s >= over_by,
+                    _ => false,
+                })
+            .min_by(|a, b| a.size.cmp(&b.size))
+            .expect("Expect a minimum")
+    );
+}