diff --git a/Cargo.toml b/Cargo.toml
index 1cb3292..12e04e8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -53,4 +53,8 @@ path = "src/day10/main.rs"
 name = "day11"
 path = "src/day11/main.rs"
 
+[[bin]]
+name = "day12"
+path = "src/day12/main.rs"
+
 [dependencies]
diff --git a/day12.txt b/day12.txt
new file mode 100644
index 0000000..148db32
--- /dev/null
+++ b/day12.txt
@@ -0,0 +1,41 @@
+abcccccccccccccccccaaaaaaaaccccccacccaaccccccccccccccccccaaaaaaaaaacccccccccccccccccccccccccccccccaaaaaaccccccccccccccccccccccccccccccccccaaaaa
+abccccccccccccccccccaaaaacccccccaaaaaaacccccccccccaaccaaaaaaaaaaaaaccccccccccccccccccccccccccccccccaaaaacccccccccccccccccccccccccccccccccaaaaaa
+abccccccccccccaaccccaaaaaacccccccaaaaaaaaccccccacaaaccaaaaaaaaaaaaaaaccccccccccccccccccaaacccccccaaaaaaaccccccccccccccccaaaccccccccccccccaaaaaa
+abccccccccacccaaccccaaaaaacccccccaaaaaaaaaccccaaaaaaaaacaaaaaaaaaaaaacccccccccccccccccccaacccccccaaaaaaaacccccccccccccccaaaccccccccccccccaccaaa
+abaacccccaaaaaaaccccaaaccacccccccaaaaaaaaaccccaaaaaaaaccccaaaaaaaaaaaccccccccccccccccaacaaaaaccccaaaaaaaacccccccccccccccaaacccccccccccccccccaaa
+abaaccccccaaaaaaaacccccccccccccccaaaaaaaaccccccaaaaaacccccaaaacaaaaccccccccccccccccccaaaaaaaaccccccaaacaccccccccccccccccaaakccaaaccccccccccccaa
+abaaacccccaaaaaaaaaccccccccccccccaaaaaaacccccccaaaaaccccccaaaccaaaaccccccccccccaacacccaaaaaccccccccaaacccccccccccccacacckkkkkkkaacccccccccccccc
+abaaacccccaaaaaaaaaccccccccccccccaccaaaaaccccccaaaaaacccccaaacaaaccccccccccccccaaaaccccaaaaacccccccccccccccccccccccaaaakkkkkkkkkacccaaaccaccccc
+abacacccccaaaaaaaccccccccccccccccccccaaaaaaaccccccaaccccccaaaaaaaaccccccccccccaaaaacccaaacaacccccccccccccccccccccccaajkkkkppkkkkccccaaaaaaccccc
+abacccccccaaaaaaacccccccccccccccccccaaaaaaaaccccccccccccccccaaaaaaccccccccccccaaaaaacccaacccccccccccccccccccccccccccjjkkooppppkllccccaaaaaccccc
+abccccccccaccaaaccccccccccccccccccccaaaaaaaacccccccccccccccccaaaaaccccccccccccacaaaacccccccccccccccccccccccccccccjjjjjjoooppppklllcacaaaaaccccc
+abcccaacccccccaaacccccccccccccccccccaaaaaaacccccccccccccccccaaaaacccccccccccccccaacaccccccccccccccccccccccccccjjjjjjjjoooopuppplllcccccaaaacccc
+abcccaacccccccccccccccccaaacccccccccccaaaaaaccccccaaaaacccccaaaaaccccccccccccaaacaaacccccaaaccccccccccccccccijjjjjjjjooouuuuuppllllcccccaaacccc
+abaaaaaaaaccccccccccccccaaaaccccccccccaacaaaccccccaaaaaccccccccccccccccccccccaaaaaaacccccaaacacccccccccccccciijjoooooooouuuuuppplllllccccaccccc
+abaaaaaaaaccccccccccccccaaaaccccccccccaacccccccccaaaaaacccccccccccccccccccccccaaaaaacccaaaaaaaacccccccccccciiiqqooooooouuuxuuuppplllllccccccccc
+abccaaaaccccccccccccccccaaaccccccccccccccccccccccaaaaaacccccccccccccccccccccccaaaaaaaccaaaaaaaacccccccccccciiiqqqqtttuuuuxxxuupppqqllllmccccccc
+abcaaaaacccaaaccccccccccccccccccccccccaccccccccccaaaaaacccccccccccccccccccccaaaaaaaaaaccaaaaaaccccccccccccciiiqqqtttttuuuxxxuuvpqqqqmmmmccccccc
+abcaacaaaccaaacaaccccccccccccccccccccaaaacaaaccccccaacccaaaaacccccccccccccccaaaaaaaaaacccaaaaacccaaaccccccciiiqqttttxxxxxxxyuvvvvqqqqmmmmcccccc
+abcacccaaccaaaaaaccccccccccccccccccccaaaaaaaacccccccccccaaaaacccccccccccccccaaacaaacccccaaaaaaccaaaacccccaaiiiqqtttxxxxxxxxyyvvvvvvqqqmmmdddccc
+abcccccccaaaaaaaccccccccccccccccccccccaaaaaaaaacccccccccaaaaaaccccccccccccccccccaaaccccccaacccccaaaacccaaaaiiiqqqttxxxxxxxyyyyyyvvvqqqmmmdddccc
+SbccccccccaaaaaccccccccaacaaccccccccaaaaaaaaaaccccccccccaaaaaaccccccccccccaaacccaaccccccccccccccaaaacccaaaaaiiiqqtttxxxxEzzyyyyvvvvqqqmmmdddccc
+abaccccccccaaaaacccccccaaaaacccccccaaaaaaaaaaaccccccccccaaaaaaccccccccccaaaaaacccccccccccccccccccccccccaaaaaiiiqqqtttxxxyyyyyyvvvvqqqmmmdddcccc
+abaacccccccaacaaaccccccaaaaaacccccccaaaaaaaaaaccccccccccccaaacccccccccccaaaaaaccccccccccccccccccccccccccaaaahhhqqqqttxxyyyyyyvvvvqqqmmmddddcccc
+abaccccccccaaccccccccccaaaaaacccaacaaccaaaaaaaaaccccccccccccccccccccccccaaaaaaccccccccccccccccccccccccccaaaachhhqqtttxwyyyyyywvrqqqmmmmdddccccc
+abaaaccccccccccccccccccaaaaaacccaaaaaccaaaaacaaaccccccccccccccccccccccccaaaaaccccaaaaccccaaaccccccccccccccccchhhppttwwwywwyyywwrrrnmmmdddcccccc
+abaaaccccccccccccccccccccaaaccccaaaaaacaaaaaaaaaccccccccaaacccccccccccccaaaaaccccaaaaccccaaaccccccccccccccccchhpppsswwwwwwwwywwrrrnnndddccccccc
+abaaacccccccccccccccccccccccccccaaaaaacccaaaaaacccccccccaaaaacccccaacccccccccccccaaaacaaaaaaaaccccccccccccccchhpppsswwwwsswwwwwrrrnneeddccccccc
+abaccccccccaaaacccccccccccccccccaaaaaaccccaaaaaaaacccccaaaaaaccaacaaacccccccccccccaaccaaaaaaaaccccccccccccccchhpppssssssssrwwwwrrrnneeecaaccccc
+abaccccccccaaaacccccccccccccccccccaaaccccaaaaaaaaacccccaaaaaaccaaaaaccccccccccccccccccccaaaaacccccccccccccccchhpppssssssssrrrwrrrnnneeeaaaccccc
+abcccccccccaaaacccccccccccccccccccccccccaaaaaaaaaaccccccaaaaacccaaaaaacccccccccccccccccaaaaaacccccccccccccccchhpppppsssooorrrrrrrnnneeeaaaccccc
+abcccccccccaaaccccccccccccccccccccccccccaaacaaacccccccccaacaacaaaaaaaacccccccccccccccccaaaaaacaaccccccccccccchhhppppppoooooorrrrnnneeeaaaaacccc
+abccccccccccccccccccccccccccccccccccccccccccaaaccaaaacccccccccaaaaacaaccccaacccccccccacaaaaaacaaccccccccccccchhhgpppppoooooooonnnnneeeaaaaacccc
+abcccccccaacccccccccccccccccccccccccccccccccaaacaaaaaccccccccccacaaaccccccaacccccccccaacaaaaaaaaaaacccccaaccccgggggggggggfooooonnneeeeaaaaacccc
+abcccccccaaacaaccccccccccccaacccccccccccccccccccaaaaaaccccaacccccaaacccaaaaaaaaccccccaaaaacaaaaaaaaccccaaacccccggggggggggfffooonneeeecaaacccccc
+abcccccccaaaaaaccccaacccccaaacccccccccccccccccccaaaaaaccccaaaccccccccccaaaaaaaacccccccaaaaaccaaaaccccaaaaaaaacccggggggggfffffffffeeeecaaccccccc
+abcccccaaaaaaaccaaaaacaaaaaaacccccccccccccccccccaaaaacccccaaaacccaaccccccaaaacccccccaaaaaaaacaaaaacccaaaaaaaaccccccccccaaaffffffffecccccccccccc
+abcaaacaaaaaaacccaaaaaaaaaaaaaaaccccccccccccccccccaaacccccaaaacaaaacaacccaaaaaccccccaaaaaaaaaaaaaaccccaaaaaacccccccccccaaacaafffffccccccccccaaa
+abaaaacccaaaaaaccaaaaacaaaaaaaaaccccccccccccaaacccccccccccaaaaaaaaacaaccaaacaacccccccccaacccaaccaaccccaaaaaaccccccccccaaaaccaaacccccccccccccaaa
+abaaaacccaacaaacaaaaacccaaaaaaacccccccccccccaaaacccccccccaaaaaaaaaaaaaccaacccacccccccccaacccccccccccccaaaaaaccccccccccaaacccccccccccccccccccaaa
+abcaaacccaacccccccaaaccaaaaaacccccccccccccccaaaaccccccaaaaaaaaaaaaaaaaaaccccccccccccccccccccccccccccccaaccaaccccccccccaaaccccccccccccccccaaaaaa
+abcccccccccccccccccccccaaaaaaaccccccccccccccaaacccccccaaaaaaaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccaaaaaa
\ No newline at end of file
diff --git a/day12_test.txt b/day12_test.txt
new file mode 100644
index 0000000..433e0d2
--- /dev/null
+++ b/day12_test.txt
@@ -0,0 +1,5 @@
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi
\ No newline at end of file
diff --git a/src/day12/main.rs b/src/day12/main.rs
new file mode 100644
index 0000000..6773a5f
--- /dev/null
+++ b/src/day12/main.rs
@@ -0,0 +1,120 @@
+use std::collections::{HashMap, VecDeque};
+use base::read_file;
+
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+struct Pos(usize, usize);
+
+impl Pos {
+    fn left(&self) -> Self { Pos(self.0 - 1, self.1) }
+    fn right(&self) -> Self { Pos(self.0 + 1, self.1) }
+    fn up(&self) -> Self { Pos(self.0, self.1 - 1) }
+    fn down(&self) -> Self { Pos(self.0, self.1 + 1) }
+
+    fn getHeight(&self, tiles: &Vec<Vec<u8>>) -> u8 {
+        return tiles[self.1][self.0];
+    }
+}
+
+fn get_positions(tiles: &Vec<Vec<u8>>, pos: Pos, width: usize, height: usize) -> Vec<Pos> {
+    let current_height = pos.getHeight(&tiles);
+    let mut positions = vec![];
+    if pos.0 > 0 {
+        positions.push(pos.left())
+    }
+    if pos.1 > 0 {
+        positions.push(pos.up());
+    }
+    if pos.0 < width - 1 {
+        positions.push(pos.right());
+    }
+    if pos.1 < height - 1 {
+        positions.push(pos.down());
+    }
+
+    let mut i = 0;
+    while i < positions.len() {
+        if positions[i].getHeight(&tiles) > current_height + 1 {
+            let _ = positions.remove(i);
+        } else {
+            i += 1;
+        }
+    }
+
+    positions
+}
+
+fn pathfinding_dijkstra(start: Pos, end: Pos, tiles: &Vec<Vec<u8>>) -> Option<u32> {
+    let height = tiles.len();
+    let width = tiles[0].len();
+    let mut discovered = HashMap::<Pos, Option<Pos>>::new();
+    discovered.insert(start, None);
+    let mut to_search = VecDeque::new();
+    to_search.push_front(start);
+
+    while !to_search.is_empty() {
+        if let Some(u) = to_search.pop_back() {
+            for position in get_positions(tiles, u, width, height) {
+                if let None = discovered.get(&position) {
+                    discovered.insert(position, Some(u));
+                    to_search.push_front(position);
+                }
+            }
+        }
+    }
+    let mut position = end;
+    let mut counter = 0;
+    loop {
+        if let Some(pre) = discovered.get(&position) {
+            if let Some(pos) = pre {
+                position = *pos;
+                counter += 1;
+            } else {
+                break;
+            }
+        } else {
+            return None;
+        }
+    }
+
+    Some(counter)
+}
+
+fn main() {
+    let lines = read_file("day12.txt");
+
+    let mut start = None;
+    let mut end = None;
+    let mut tiles = vec![];
+    let mut zero_height_tiles = vec![];
+
+    for (y, line) in lines.iter().enumerate() {
+        tiles.push(vec![]);
+        for (x, c) in line.bytes().enumerate() {
+            match c {
+                83 => {
+                    let pos = Pos(x, y);
+                    start = Some(pos);
+                    zero_height_tiles.push(pos);
+                    tiles[y].push(0);
+                }
+                69 => {
+                    end = Some(Pos(x, y));
+                    tiles[y].push(25);
+                }
+                _ => {
+                    let height = c - 'a' as u8;
+                    tiles[y].push(height);
+                    if height == 0 {
+                        zero_height_tiles.push(Pos(x, y));
+                    }
+                }
+            }
+        }
+    }
+
+    println!("Task 1: {}", pathfinding_dijkstra(start.unwrap(), end.unwrap(), &tiles).unwrap());
+
+    let task2 = zero_height_tiles.iter().filter_map(|start| pathfinding_dijkstra(*start, end.unwrap(), &tiles)).min().unwrap();
+
+    println!("Task 2: {}", task2);
+}
\ No newline at end of file