day 12 solution

2022/Cargo.lock

@@ -13,4 +13,43 @@ name = "aoc2022"
 version = "0.1.0"
 dependencies = [
  "anyhow",
+ "petgraph",
+]
+
+[[package]]
+name = "autocfg"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
+
+[[package]]
+name = "fixedbitset"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ce7134b9999ecaf8bcd65542e436736ef32ddca1b3e06094cb6ec5755203b80"
+
+[[package]]
+name = "hashbrown"
+version = "0.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
+
+[[package]]
+name = "indexmap"
+version = "1.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1885e79c1fc4b10f0e172c475f458b7f7b93061064d98c3293e98c5ba0c8b399"
+dependencies = [
+ "autocfg",
+ "hashbrown",
+]
+
+[[package]]
+name = "petgraph"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6d5014253a1331579ce62aa67443b4a658c5e7dd03d4bc6d302b94474888143"
+dependencies = [
+ "fixedbitset",
+ "indexmap",
 ]

2022/Cargo.toml

@@ -11,3 +11,4 @@ test_input = []
 
 [dependencies]
 anyhow = "1.0.66"
+petgraph = "0.6.2"

2022/day12.txt

@@ -0,0 +1,41 @@
+abcccccccccccccccccaaccccccccccccaaaaaaaacccccccccccaaaaaccccaaaaaaccaaaaaaaaaaaaaaaaaccccccccccccccccaaacccccaaaaaaaacccaaaccccccccccccccccccccccccccccccccccccccccccccccccccaaaaa
+abccccccccccccccccaaacaacccccccccccaaaacccccccccccccaaaaaacccaaaaaaccaaaaaaaaaaaaaaaaaaaacccccccccaaacaaacccccaaaaaaaaaccaaaaccccccccccccccccccccccccccccccccccccccccccccccccaaaaaa
+abcccccccccccccccccaaaaacccccccccccaaaaaccccccccccccaaaaaaccccaaaacccaaaacccaaaaaaaaaaaaacccccccccaaaaaaaaaacccaaaaaaaaccaaaaccccccccccccccccccccccccccccccccccaaacccccccccccaaaaaa
+abcccccccccccccccaaaaaacccccccccccaaacaaccaaccccccccaaaaaaccccaaaacccaaaccccaaaaaaaaaaaaaccccccccccaaaaaaaaaccaaaaaacccccaaacccccccccccccccccccccccccccccccccccaaaccccccccccccccaaa
+abcccccccccccccccaaaaaaaacccccccccaacccacaaacaacccccccaaccccccaccaccccccccaaaaaaaaaaaaccccccccccccccaaaaaaacccaaaaaaacccccccccccccaacccccccccccccccccccccccccccaaaccccccccccccccaaa
+abcccccccccccccccaacaaaaacccccccccccccccccaaaaacccccccccccccccccccccccccccaaaaaaaaaaaaccccccccccccccaaaaaaccccaaccaaacccccccccccaaaaaaccccccccccccccccccccccccccdccccccccccccccccaa
+abccaacccccccaaacccaaacaccccccccccaaacccaaaaaaccccccccccccccccccccccccccccaaacccaaaaaacaaaaccccccccaaaaaaaccccccccaaacccccccccccaaaaaacccccccccccccccccllllllcccdddddcccccccccccccc
+abaaaacccacccaaccccaacccccccccccccaaacccaaaaaaaacccccccccccccccccaaccccccccacccaaaaccccaaaaccccccccaaacaaaccccccccccccccccccccccaaaaaaccccccccccccccccllllllllldddddddddddccaaccccc
+abaaaaccaaaaaaaacccccccccccccccaaaaaaaacaacaaaaacccccccccccccccccaaacccccccaaacaaccccccaaaacccccccccccccaaccccccccccccccccccccccaaaaaccccccccccccccccclllllllllldddddddddeeaaaccccc
+abaaaccccaaaaaaaaccccccccaaacccaaaaaaaacccaaacccccccccccccccccaaaaaaaaccccccaaaaacccccccaacccccccccccccccccccccccccccccccccccccccaaaaccccaaaccccccccckllppppplllmmmmmmmdeeeeaaccccc
+abaaaacccaaaaaaaaacccccaaaaaaccccaaaaaccccaaccccccccccccccccccaaaaaaaaccccccaaaaaaacccccccccccccccccccccccccccccccccccccccccccccccccccccaaaacccccccckklpppppppplmmmmmmmmmeeeeaccccc
+abaaaacccaaaaaaaaacccccaaaaaacccaaaaaaccccccccaacccccccccccccccaaaaaaccccccaaaaaaaacccccccccccccccccccccccccccccccccccccccccccccccccccccaaaacccccccckkkppppppppqmmmmmmmmmmeeeaacccc
+abaaaaaccaaaaaaaaccccccaaaaaacccaaaaaaccccccacaaaacccccccccccccaaaaaaccccccaaaaaaaaccccccccaaaaccccccccaaacccccccccccccccccccccccccccccccaaacccccccckkkpppuuuppqqqqqqqqmmmeeeeacccc
+abacccccaaaaaaaccccccccaaaaaccccaccaaaccccccaaaaaacccccacccccccaaaaaaccccccaaaaaacaaaccccccaaaaccccccccaaaacccccccccccccccccccccccccccccccccccccccckkkpppuuuuuuqqqqqqqqqnnneeeccccc
+abcccccccaccaaaccccccccaaaaacccccccccccccccccaaaacccaaaacccccccaacaaacccccccccaaacaaaaaccccaaaaccccccccaaaaccccccccccccccccccccccccccccccccccccccckkkkpppuuuuuuuqvvvvqqqnnneeeccccc
+abcccccccccccaaacaaccccccccccccccccccccccccccaaaacccaaaaaacccccccccccccccccccccccaaaaaaccccaaacccccccccaaaccccccccccccccccccccccccccccccccccccccckkkkrrpuuuxxxuvvvvvvvqqnnneeeccccc
+abcccccccccccccccaacaaaccccccccccccccccccccccaacaacccaaaaacccccccccccccccccccccccaaaaaaccccccccccccccccccccccccccccccccccccccccccccccccccccccccckkkkrrrruuxxxxuvvvvvvvqqnnneeeccccc
+abcccccccccccccccaaaaacccccccccccccccccccccccccccaccaaaaacccccaaccccccccccccccccccaaaaaccccccccccccccccaaaccccccccccccccaaacccccccccccccccccccckkkkrrrruuuxxxxyyyyyvvvqqnnneecccccc
+abcccccccccccccaaaaaacccccccccccaacaacccccccccccaaaaaaaaacccacaaaacaaccaaccccccccaaacaaccccccccccaaccccaaaaaacccaacaacccaaacacccccccccccccccccjjkkrrrruuuuuxxxyyyyyvvqrqnneffcccccc
+abcccccccccccccaaaaaaaacccaaacccaaaaaccccccaacccaaaaaaaaacccaaaaaacaaaaaaccccccccaaacaaacccccccaaaaaacaaaaaaacccaaaaacaaaaaaaaccccccccccccccccjjjrrrtttuuxxxxxyyyyyvvrrnnnfffcccccc
+SbccccccccccccccccaaaaacccaaaaccaaaaaaccccaaaaaacaaaaaaaaacccaaaacccaaaaaccccccccaaaaaaacccccccaaaaaaaaaaaaaaccaaaaaccaaaaaaaaccccccccccccccccjjjrrrtttxxxEzzzzyyyvvrrrnnnfffcccccc
+abccccccccccaaaccaaccaacccaaaaccaaaaaacccccaaaaacaaaaaaaaacccaaaaccaaaaaacccccccccaaaaaaccccccccaaaacaaaaaaacccaaaaaaccaaaaaacccccccccccccccccjjjrrrtttxxxxxyyyyyyvvrrrnnnfffcccccc
+abcccccccccaaaaccaacccccccaaacccaaaaaacccaaaaaaaaaaaaaaaaacccaacacaaaaaaaacccccaaaaaaaacccccccccaaaacccaaaaaaccccaaaacccaaaaacccccccccccccccccjjjrrrtttxxxxxyyyyyyywvrrnnnfffcccccc
+abcccccccccaaaacccccccccccccccccccaaaccccaaaaaaaaaaaaaaaaaacccccccaaaaaaaacccccaaaaaaaaaccccccccaccacccaaaaaaccccacccccaaaaaacccccccccccccccccjjjrrrrttttxxxyyyyyyywwrrroooffcccccc
+abccccccccccaaaccccccccccccccccccccccccccaaaaaaaaaccaaaaaaaccccccccccaaccccccccaaaaaaaaaaccccccccccccccaacccccccccccccccaaccccccccccccccccccccjjjjqqqqttttxxyywwwwwwwwrrooofffccccc
+abcccccccccccccccccccccccccccccccccccccccccaaacacccccaaaaccccccccccccaacccccccccccaaacaaacccccccccccccccccccccccccccccaaacccccccccccccccccccaacjjjjqqqqqttwwwwwwwwwwwrrrooofffccccc
+abcccccccccccccccccccccccccccccccccccccccccaaccccccccccaacccccccccccccccccccccccccaaacccccccccccccccccccccccccccccccccaaacccccccccccccccccaaaaaajjjjqqqqttwwwwwwsswwrrrrooofffccccc
+abcccccaaaaccccccccccccccaacaaccccccccccccccccccccccccccccccccccccccccccccccccccccaacccccccccccccccccccccccccccccccaaaaaaaaccaaaacccccccccaaaaaacjjjiqqqtttwwwwsssssrrrrooofffccccc
+abccccaaaaaccccccccccccccaaaaacccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccaaaaaaaaccaaaaacccccccccaaaaacciiiiqqttswwwssssssrrroooogffccccc
+abccccaaaaaacccccccccccccaaaaaacccaaaccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccaaaaaccaaaaaaccccccccaaaaacccciiiqqqssssssspppooooooogggaccccc
+abccccaaaaaaccccccccaacccaaaaaaccccaacccccccccccccccccccccccccccccccccaaaaccccccccccccccccccccccccccccccccccccccccccaaaaaaccaaaaaaccccccccaaaaaccccciiiqqsssssspppppoooooggggaacccc
+abccccaaaaaccccccaaaaacccaaaaaacaacaaaaaccccccccccccccccccccaacccccccaaaaacccccccccccaaaccccccccccccccccccccccccccccaaaaaacccaaaaacccccccccacccccccciiiqqqpssspppppgggggggggaaacccc
+abccccccaaacccccccaaaaaccccaaaccaaaaaaaacccccccaacccccccaaccaacccccccaaaaaacccccccccaaaacccccccccccaaaaccccccccccccaaccaaacccaaacccccaaacaaaccccccccciiqqppppppphhhggggggggaaaacccc
+abccccccccccccccccaaaaaccccccccccaaaaaccccccccaaacaaccccaaaaaacccccccaaaaaaaccccccccaaaacccccccccccaaaacccccccccaaaaaacccccccccccccccaaaaaaaccccccccciiippppppphhhhggggggcaaacccccc
+abaacccccccccccccaaaaaccccccccccccaaaaaccccccccaaaaacccccaaaaaaacccccaaaaacaaacccccccaaacccccccccccaaaacccccccccaaaaacccccccccccccccccaaaaaacccccccccciiiippphhhhhhcccccccaaacccccc
+abaacccccccccccccccaaacccccccccccaaacaaccccccaaaaaaccccccaaaaaaacccaaccaaacaaaaccaaaccccccccccccccccaaacccccccccaaaaaaacccccccccccccccaaaaaaaacccccccciiihhhhhhhhaaaccccccccccccccc
+abaaccccccccccccccccccccccccccccccaacccccccccaaaaaaaacccaaaaaaccaaaaaacccccaaaacaaaaaccccccccccccccccccccccccccaaaaaaaaccccccccccccccaaaaaaaaaccccccccciihhhhhhcaaaacccccccccccccca
+abaaccccccccccccccccccccccccccccccccaacccccccaacaaaaacccaaaaaaccaaaaacccccccaaaaaaaacccccccccccccccccccccccccccaaaaaaaacccccccccaaacaaaaaaaaaacccccccccccchhhaccccaacccccccccccccca
+abaaccccccccccccccccccccccccccccccccaaaaaaccccccaaccccccccccaaccaaaaaaacccccaaaaaaaccccccccccccccccccccccccaaaccacaaacccccccccccaaaaaaacaaacaaaaaacccccccccaaacccccccccccccccaaaaaa
+abccccccccccccccccccccccccccccccccccaaaaaccccccaaccccccccccccccaaaaaaaacaaaaaaaaaaccccccccccccccccccccccccaaaaaaccaaaccccccccccccaaaaaacaaacaaaaaacccccccccaaaccccccccccccccccaaaaa
+abccccccccccccccccccccccccccccccccaaaaaaaacccccccccccccccccccccaaaaaaaacaaaaaaaaaaaaacccccccccccccccccccccaaaaaacccccccccccccccaaaaaaaaaaaaaaaaaacccccccccccccccccccccccccccccaaaaa

2022/src/days/day12.rs

@@ -0,0 +1,141 @@
+use anyhow::{anyhow, Result};
+use petgraph::algo::astar;
+use petgraph::dot::{Config, Dot};
+use petgraph::graph::{DefaultIx, NodeIndex};
+use petgraph::prelude::*;
+//use petgraph::{Directed, Graph};
+use std::collections::HashMap;
+use std::fs;
+use std::fs::File;
+use std::io::Write;
+use std::path::Path;
+
+type Map = [[i32; 180]; 180];
+type WGraph = Graph<Coord, i32, Directed, DefaultIx>;
+type Coord = (usize, usize);
+type Indexes = HashMap<Coord, NodeIndex<DefaultIx>>;
+
+pub fn run() -> Result<()> {
+    #[cfg(not(feature = "test_input"))]
+    let file_contents = fs::read_to_string("day12.txt")?;
+
+    #[cfg(feature = "test_input")]
+    let file_contents = fs::read_to_string("tests/day12.txt")?;
+
+    let mut world: Map = [[0; 180]; 180];
+    let mut rows = 0;
+    let mut cols = 0;
+    let mut graph: WGraph = Graph::new();
+    let mut indexes: Indexes = HashMap::with_capacity(180 * 180);
+    let mut start: Coord = (0, 0);
+    let mut end: Coord = (0, 0);
+    let mut p2starts: Vec<NodeIndex<DefaultIx>> = Vec::new();
+
+    for line in file_contents.lines() {
+        cols = 0;
+        for char in line.chars() {
+            world[rows][cols] = get_height(&char);
+            let index = graph.add_node((rows, cols));
+            if world[rows][cols] == 1 {
+                p2starts.push(index);
+            }
+            indexes.insert((rows, cols), index);
+            if char == 'S' {
+                start = (rows, cols);
+            } else if char == 'E' {
+                end = (rows, cols);
+            }
+            cols += 1;
+        }
+        rows += 1;
+    }
+    println!("finding distance between {:?} and {:?}", start, end);
+
+    for x in 0..rows {
+        for y in 0..cols {
+            let cur = (x, y);
+            if cur == end {
+                continue;
+            }
+            if x > 0 {
+                check_coord(&mut graph, &world, &indexes, &cur, &(x - 1, y));
+            }
+            if x < rows - 1 {
+                check_coord(&mut graph, &world, &indexes, &cur, &(x + 1, y));
+            }
+            if y > 0 {
+                check_coord(&mut graph, &world, &indexes, &cur, &(x, y - 1));
+            }
+            if y < cols - 1 {
+                check_coord(&mut graph, &world, &indexes, &cur, &(x, y + 1));
+            }
+        }
+    }
+
+    let dotpath = Path::new("day12.dot");
+    let mut file = match File::create(&dotpath) {
+        Err(why) => return Err(anyhow!("could not write file {}", why)),
+        Ok(file) => file,
+    };
+    match file
+        .write_all(format!("{:?}", Dot::with_config(&graph, &[Config::EdgeNoLabel])).as_bytes())
+    {
+        Err(why) => return Err(anyhow!("could not write dot file {}", why)),
+        Ok(_) => println!("wrote day12.dot"),
+    };
+
+    let start_index = indexes.get(&start).unwrap();
+    let end_index = indexes.get(&end).unwrap();
+    #[allow(unused_variables)]
+    if let Some((len, path)) = astar(
+        &graph,
+        *start_index,
+        |finish| finish == *end_index,
+        |e| *e.weight(),
+        |_| 0,
+    ) {
+        println!("part one steps ({})", len);
+        #[cfg(feature = "test_input")]
+        for n in path.iter() {
+            println!("{:?}", graph.node_weight(*n).unwrap());
+        }
+    }
+
+    let mut min_len: i32 = rows as i32 * cols as i32;
+    for s in p2starts.iter() {
+        if let Some((len, _)) = astar(
+            &graph,
+            *s,
+            |finish| finish == *end_index,
+            |e| *e.weight(),
+            |_| 0,
+        ) {
+            if len < min_len {
+                min_len = len;
+            }
+        }
+    }
+    println!("part 2 minimum steps {}", min_len);
+    Ok(())
+}
+
+fn check_coord(graph: &mut WGraph, world: &Map, indexes: &Indexes, source: &Coord, dest: &Coord) {
+    let h = world[source.0][source.1];
+    let hi = indexes.get(source).unwrap();
+    let d = world[dest.0][dest.1];
+    let di = indexes.get(dest).unwrap();
+
+    if (d > h && d == h + 1) || d == h || d < h {
+        graph.update_edge(*hi, *di, 1);
+    }
+}
+
+fn get_height(c: &char) -> i32 {
+    if *c == 'S' {
+        1
+    } else if *c == 'E' {
+        27
+    } else {
+        *c as i32 - 96
+    }
+}

2022/src/days/mod.rs

@@ -1,6 +1,7 @@
 pub mod day1;
 pub mod day10;
 pub mod day11;
+pub mod day12;
 pub mod day2;
 pub mod day3;
 pub mod day4;

2022/src/main.rs

@@ -45,6 +45,9 @@ fn run_day(number: i32) -> Result<()> {
         11 => {
             days::day11::run()?;
         }
+        12 => {
+            days::day12::run()?;
+        }
         _ => return Err(anyhow!("Invalid day provided")),
     }
     Ok(())

2022/tests/day12.txt

@@ -0,0 +1,5 @@
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi