day13pt2 (always love insertion sort)

src/bin/13.rs

@@ -1,5 +1,5 @@
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, PartialEq)]
 pub enum PacketVal {
     scalar(u32),
     list(Vec<PacketVal>)
@@ -31,7 +31,6 @@ impl PacketVal {
         if left.len() < other.len() {
             return Cmp::good
         } else if left.len() == other.len() {
-            // println!("moo");
             return Cmp::idk
         } else {
             return Cmp::bad
@@ -60,6 +59,22 @@ impl PacketVal {
     }
 }
 
+pub fn sorted(packets: &mut Vec<PacketVal>) {
+    let mut idx = 0;
+    let mut curr_min_idx = 0;
+
+    while idx < packets.len() {
+        curr_min_idx = idx;
+        for search_idx in (idx + 1)..packets.len() {
+            if let Cmp::good = packets[search_idx].lt(&packets[curr_min_idx]) {
+                curr_min_idx = search_idx;
+            }
+        }
+        packets.swap(idx, curr_min_idx);
+        idx += 1;
+    }
+}
+
 
 pub fn parse_line(line: &str) -> PacketVal {
     let mut pack_stack: Vec<PacketVal> = Vec::new();
@@ -121,8 +136,49 @@ pub fn part_one(input: &str) -> Option<u32> {
     Some(count)
 }
 
-pub fn part_two(input: &str) -> Option<u32> {
-    None
+pub fn part_two(input: &str) -> Option<usize> {
+    let mut lines = input.lines();
+    let mut packets: Vec<PacketVal> = Vec::new();
+    
+    loop {
+        let left_line = lines.next().unwrap();
+        let left = parse_line(left_line);
+        
+        let right_line = lines.next().unwrap();
+        let right = parse_line(right_line);
+        
+
+        packets.push(left);
+        packets.push(right);
+
+        
+        match lines.next() {
+            Some(_) => continue,
+            _ => break
+        }
+    }
+
+    let marker_one = parse_line("[[2]]");
+    let marker_two = parse_line("[[6]]");
+
+    packets.push(marker_one.clone());
+    packets.push(marker_two.clone());
+
+    sorted(&mut packets);
+
+    let mut first_marker_idx = 0;
+    let mut second_marker_idx = 0;
+
+    for (idx, packet) in packets.iter().enumerate() {
+        // println!("{:?}", packet);
+        if *packet == marker_one {
+            first_marker_idx = idx + 1;
+        } else if *packet == marker_two {
+            second_marker_idx = idx + 1;
+        }
+    }
+
+    Some(first_marker_idx * second_marker_idx)
 }
 
 fn main() {
@@ -144,6 +200,6 @@ mod tests {
     #[test]
     fn test_part_two() {
         let input = advent_of_code::read_file("examples", 13);
-        assert_eq!(part_two(&input), None);
+        assert_eq!(part_two(&input), Some(140));
     }
 }