Add day 13

src/day13/main.rs

@@ -1,17 +1,37 @@
-use std::fmt::Display;
+use std::fmt::{Display, Formatter};
 use base::read_file;
 
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Debug, Eq, PartialEq, Clone)]
 struct List {
     elements: Vec<ListElement>,
 }
 
-#[derive(Debug, Eq, PartialEq)]
+#[derive(Debug, Eq, PartialEq, Clone)]
 enum ListElement {
     Number(u32),
     Sublist(List),
 }
 
+impl Display for List {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        f.write_str("[")?;
+        for (idx, element) in self.elements.iter().enumerate() {
+            match element {
+                ListElement::Number(n) => {
+                    write!(f, "{}", n)?;
+                }
+                ListElement::Sublist(sub) => {
+                    write!(f, "{}", sub)?;
+                }
+            }
+            if idx != self.elements.len() - 1 {
+                f.write_str(",")?;
+            }
+        }
+        f.write_str("]")
+    }
+}
+
 fn add_to_list(next: &Vec<char>, start: usize) -> (List, usize) {
     let mut list = List { elements: vec![] };
     let mut index = start;
@@ -26,6 +46,7 @@ fn add_to_list(next: &Vec<char>, start: usize) -> (List, usize) {
                 let (sublist, new_idx) = add_to_list(next, index + 1);
                 index = new_idx;
                 list.elements.push(ListElement::Sublist(sublist));
+                continue;
             }
             ']' => {
                 return (list, index + 1);
@@ -103,18 +124,56 @@ fn are_in_right_order(lhs: &List, rhs: &List) -> Option<bool> {
     }
 }
 
+fn create_list(str: &str) -> List {
+    return add_to_list(&mut str.chars().collect::<Vec<_>>(), 0).0;
+}
+
 fn main() {
     let lines = read_file("day13.txt");
     let mut lists = vec![];
     for line in lines {
         if !line.is_empty() {
-            lists.push(add_to_list(&mut line.chars().collect::<Vec<_>>(), 0).0);
+            lists.push(create_list(&line));
+            let line = line.trim_end();
+            let last_line = lists.last().unwrap();
+            let test_result = last_line.to_string() == line;
+            if test_result {
+                println!("Compare: {} with {}", line, last_line);
+            } else {
+                panic!("Parser error!");
+            }
         }
     }
     let task1 = lists.chunks_exact(2).enumerate().filter(|(_, chunk)| are_in_right_order(&chunk[0], &chunk[1]).unwrap()).fold(0, |acc, (idx, _)| {
-        println!("Found machting pair at: {idx}");
+        println!("Found matching pair at: {idx}");
         acc + idx + 1
     });
 
     println!("Task1: {task1}");
+
+    let list_2 = create_list("[[2]]");
+    let list_6 = create_list("[[6]]");
+
+    lists.push(list_2.clone());
+    lists.push(list_6.clone());
+
+    for idx in 0..lists.len() {
+        for list in (idx + 1)..lists.len() {
+            if !are_in_right_order(&lists[idx], &lists[list]).unwrap() {
+                lists.swap(idx, list);
+            }
+        }
+    }
+
+    let mut index_2 = 0;
+    let mut index_6 = 0;
+    for (idx, list) in lists.iter().enumerate() {
+        if *list == list_2 {
+            index_2 = idx + 1;
+        } else if *list == list_6 {
+            index_6 = idx + 1;
+        }
+    }
+
+    println!("Found index {} and index {}. Result is {}", index_2, index_6, index_2 * index_6);
 }