2021/src/day12.rs

@@ -1,7 +1,24 @@
-use std::collections::HashMap;
+use std::{
+    collections::HashMap,
+    fmt::{Debug, Error, Formatter},
+    num::ParseIntError,
+    ops::{Index, IndexMut},
+    str::FromStr,
+};
 
 use anyhow::Result;
-use aoc_runner_derive::aoc;
+use aoc_runner_derive::{aoc, aoc_generator};
+use thiserror::Error;
+
+struct Node {
+    name: String,
+    small: bool,
+    neighbors: Vec<usize>,
+}
+
+struct Graph {
+    nodes: Vec<String>,
+}
 
 fn search(node: &str, nodes: &HashMap<&str, Vec<&str>>, path: String, paths: &mut Vec<String>) {
     if node == "end" {
@@ -10,9 +27,11 @@ fn search(node: &str, nodes: &HashMap<&str, Vec<&str>>, path: String, paths: &mu
     }
     for neighbor in &nodes[node] {
         // If lowercase.
-        if neighbor.as_bytes()[0] & 0x20 != 0 && path.contains(neighbor) {
+        if neighbor.as_bytes()[0] & 0x20 != 0 {
+            if path.contains(neighbor) {
                 continue;
             }
+        }
         search(neighbor, nodes, format!("{},{}", path, neighbor), paths);
     }
 }
@@ -20,6 +39,7 @@ fn search(node: &str, nodes: &HashMap<&str, Vec<&str>>, path: String, paths: &mu
 fn paths(nodes: &HashMap<&str, Vec<&str>>) -> usize {
     let mut paths = Vec::new();
     search("start", nodes, "start".to_string(), &mut paths);
+    //dbg!(&paths);
     paths.len()
 }
 
@@ -28,78 +48,19 @@ fn part1(input: &str) -> Result<usize> {
     let mut nodes = HashMap::new();
     input.lines().for_each(|p| {
         let (n1, n2) = p.split_once('-').expect("missing dash");
-        nodes.entry(n1).or_insert_with(Vec::new).push(n2);
-        nodes.entry(n2).or_insert_with(Vec::new).push(n1);
+        nodes.entry(n1).or_insert(Vec::new()).push(n2);
+        nodes.entry(n2).or_insert(Vec::new()).push(n1);
     });
     Ok(paths(&nodes))
 }
 
-fn search2<'a>(
-    node: &str,
-    nodes: &HashMap<&'a str, Vec<&'a str>>,
-    path: &[&'a str],
-    paths: &mut Vec<Vec<&'a str>>,
-    double: &'a str,
-    smalls: &[&'a str],
-) {
-    if node == "end" {
-        paths.push(path.to_vec());
-        return;
-    }
-    for neighbor in &nodes[node] {
-        // If lowercase.
-        if neighbor.as_bytes()[0] & 0x20 != 0 {
-            if neighbor == &double {
-                // Allow two passes for this small node.
-                if path.iter().filter(|p| p == &neighbor).count() >= 2 {
-                    continue;
-                }
-            } else {
-                // Only allow one pass for this small node.
-                if path.contains(neighbor) {
-                    continue;
-                }
-            }
-        }
-        let mut child_path = path.to_vec();
-        child_path.push(neighbor);
-        search2(neighbor, nodes, &child_path, paths, double, smalls);
-    }
-}
-fn paths2(nodes: &HashMap<&str, Vec<&str>>) -> usize {
-    let mut paths = Vec::new();
-    let smalls: Vec<_> = nodes
-        .keys()
-        .filter(|n| n.as_bytes()[0] & 0x20 != 0)
-        .filter(|&n| n != &"start" && n != &"end")
-        .cloned()
-        .collect();
-
-    for double in &smalls {
-        search2(
-            "start",
-            nodes,
-            &["start"],
-            &mut paths,
-            double,
-            smalls.as_slice(),
-        );
-    }
-    paths.sort();
-    paths.dedup();
-    paths.len()
-}
-
+/*
 #[aoc(day12, part2)]
-fn part2(input: &str) -> Result<usize> {
-    let mut nodes = HashMap::new();
-    input.lines().for_each(|p| {
-        let (n1, n2) = p.split_once('-').expect("missing dash");
-        nodes.entry(n1).or_insert_with(Vec::new).push(n2);
-        nodes.entry(n2).or_insert_with(Vec::new).push(n1);
-    });
-    Ok(paths2(&nodes))
+fn part2(input: &[u64]) -> Result<u64> {
+todo!("part2");
+Ok(0)
 }
+*/
 
 #[cfg(test)]
 mod tests {
@@ -122,19 +83,14 @@ b-end
         Ok(())
     }
 
+    /*
     #[test]
     fn test_part2()->Result<()> {
     let input = r#"
-start-A
-start-b
-A-c
-A-b
-b-d
-A-end
-b-end
     "#
     .trim();
-        assert_eq!(part2(input)?, 36);
+    assert_eq!(part2(&parse(input)?)?, u64::MAX);
     Ok(())
     }
+    */
 }