diff --git a/inputs/day15.txt b/inputs/day15.txt
new file mode 100644
index 0000000..544783a
--- /dev/null
+++ b/inputs/day15.txt
@@ -0,0 +1,100 @@
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diff --git a/inputs/sample.txt b/inputs/sample.txt
index b5594dd..ab80887 100644
--- a/inputs/sample.txt
+++ b/inputs/sample.txt
@@ -1,18 +1,10 @@
-NNCB
-
-CH -> B
-HH -> N
-CB -> H
-NH -> C
-HB -> C
-HC -> B
-HN -> C
-NN -> C
-BH -> H
-NC -> B
-NB -> B
-BN -> B
-BB -> N
-BC -> B
-CC -> N
-CN -> C
+1163751742
+1381373672
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diff --git a/src/bin/day15.rs b/src/bin/day15.rs
new file mode 100644
index 0000000..b5b92fc
--- /dev/null
+++ b/src/bin/day15.rs
@@ -0,0 +1,120 @@
+use std::collections::HashMap;
+use std::collections::HashSet;
+use std::error::Error;
+use std::fs::File;
+use std::io::{self, BufRead};
+use std::vec::Vec;
+
+fn get_risk(x: i32, y: i32, map: &Vec<Vec<u32>>) -> Option<u32> {
+    let tw = map[0].len() as i32;
+    let th = map.len() as i32;
+    let mw = tw * 5;
+    let mh = th * 5;
+
+    if y >= 0 && y < mh as i32 && x >= 0 && x < mw as i32 {
+        let tile_x = x / tw;
+        let tile_y = y / th;
+        let mx = x % tw;
+        let my = y % th;
+
+        let mut risk = map[my as usize][mx as usize] + tile_x as u32 + tile_y as u32;
+        while risk > 9 {
+            risk -= 9;
+        }
+
+        Some(risk)
+    } else {
+        None
+    }
+}
+
+fn do_the_dijkstra(
+    start_x: i32,
+    start_y: i32,
+    target_x: i32,
+    target_y: i32,
+    map: &Vec<Vec<u32>>,
+) -> u32 {
+    let mut unexplored: HashSet<(i32, i32)> = HashSet::new();
+    let mut path_risk: HashMap<(i32, i32), u32> = HashMap::new();
+    path_risk.insert((start_x, start_y), 0);
+    //let mut predecessors: HashMap<(i32, i32), (i32, i32)> = HashMap::new();
+
+    for x in 0..target_x + 1 {
+        for y in 0..target_y + 1 {
+            unexplored.insert((x as i32, y as i32));
+        }
+    }
+
+    while !unexplored.is_empty() {
+        let mut cur_node: Option<(i32, i32)> = None;
+
+        let known_nodes: HashSet<(i32, i32)> = path_risk.keys().cloned().collect();
+        let candidates: HashSet<(i32, i32)> =
+            unexplored.intersection(&known_nodes).cloned().collect();
+
+        for candidate in candidates.iter() {
+            if let Some(node) = cur_node {
+                if path_risk[candidate] < path_risk[&node] {
+                    cur_node = Some(*candidate);
+                }
+            } else {
+                cur_node = Some(*candidate);
+            }
+        }
+
+        let cur_node = cur_node.unwrap();
+
+        println!("{:?} {}", cur_node, unexplored.len());
+
+        unexplored.remove(&cur_node);
+
+        if cur_node.0 == target_x && cur_node.1 == target_y {
+            println!("Found my target!");
+            break;
+        }
+
+        for (dx, dy) in [(1, 0), (0, 1), (-1, 0), (0, -1)] {
+            let neighboor = (cur_node.0 + dx, cur_node.1 + dy);
+            if let Some(enter_risk) = get_risk(neighboor.1, neighboor.0, &map) {
+                let alt_risk = path_risk[&cur_node] + enter_risk;
+                if !path_risk.contains_key(&neighboor) {
+                    path_risk.insert(neighboor, alt_risk);
+                } else if alt_risk < path_risk[&neighboor] {
+                    path_risk.insert(neighboor, alt_risk);
+                }
+            }
+        }
+    }
+
+    path_risk[&(target_x, target_y)]
+}
+
+fn main() -> Result<(), Box<dyn Error>> {
+    let file = File::open("inputs/day15.txt")?;
+    let map: Vec<Vec<u32>> = io::BufReader::new(file)
+        .lines()
+        .map(|l| {
+            l.unwrap()
+                .chars()
+                .map(|c| c.to_string().parse().unwrap())
+                .collect()
+        })
+        .collect();
+
+    let target_x = map[0].len() as i32 - 1;
+    let target_y = map.len() as i32 - 1;
+
+    let answer1 = do_the_dijkstra(0, 0, target_x, target_y, &map);
+
+    let target2_x = (map[0].len() * 5) as i32 - 1;
+    let target2_y = (map.len() * 5) as i32 - 1;
+
+    let answer2 = do_the_dijkstra(0, 0, target2_x, target2_y, &map);
+
+    println!("Answer1: {}", answer1);
+
+    println!("Answer2: {}", answer2);
+
+    Ok(())
+}