Add day 7

Cargo.toml

@@ -33,4 +33,8 @@ path = "src/day5/main.rs"
 name = "day6"
 path = "src/day6/main.rs"
 
+[[bin]]
+name = "day7"
+path = "src/day7/main.rs"
+
 [dependencies]

day7_test.txt

@@ -0,0 +1,23 @@
+$ 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

src/day7/main.rs

@@ -0,0 +1,78 @@
+use std::collections::HashMap;
+use base::read_file;
+
+fn generate_parent_paths(vec: &Vec<String>) -> Vec<String> {
+    let mut parent = "/".to_owned();
+    let mut result = vec![];
+
+    result.push(parent.clone());
+    for x in vec {
+        parent = parent + x + "/";
+        result.push(parent.clone());
+    }
+    result
+}
+
+fn main() {
+    let lines = read_file("day7.txt");
+
+    let mut current_dir = vec![];
+    let mut sizes = HashMap::new();
+    for output in lines {
+        if output.starts_with("$ cd") {
+            let mut output = output.split("$ cd");
+            output.next();
+            let sub_folder = output.next().unwrap().trim().to_owned();
+            if sub_folder != "/" {
+                if sub_folder == ".." {
+                    current_dir.remove(current_dir.len() - 1);
+                } else {
+                    current_dir.push(sub_folder);
+                }
+            }
+        } else if output.starts_with("$ ls") { } else {
+            if output.starts_with("dir") { } else {
+                let mut split = output.split_whitespace();
+                let size = split.next().unwrap().parse::<usize>().unwrap();
+                for parent in generate_parent_paths(&current_dir) {
+                    *sizes.entry(parent).or_insert_with(||0) += size;
+                }
+            }
+        }
+    }
+
+    let mut size_counter = 0;
+
+    for (k,v) in &sizes {
+        if *v <= 100000 {
+            size_counter += v;
+        }
+    }
+
+    println!("Sizes of all smaller 100000: {size_counter}");
+
+    let space_left = 70000000 - sizes["/"];
+    let space_req = 30000000 - space_left;
+    println!("Available space: {space_left}");
+    println!("Space required: {space_req}");
+
+    let mut found: Option<(usize, String)>= None;
+    for (k, v) in &sizes {
+        if *v >= space_req {
+            match &found {
+                None => {
+                    found = Some((*v, k.clone()));
+                }
+                Some((size, _)) => {
+                    if *v < *size {
+                        found = Some((*v, k.clone()))
+                    }
+                }
+            }
+        }
+    }
+
+    if let Some((size, name)) = found {
+        println!("Would remove directory {name} with size {size}");
+    }
+}