diff --git a/2021/src/day09.rs b/2021/src/day09.rs
index fdd6e81..33fdecd 100644
--- a/2021/src/day09.rs
+++ b/2021/src/day09.rs
@@ -1,56 +1,6 @@
 use std::cmp::Reverse;
 use std::io::Read;
 
-struct LowPointsIter<'a> {
-    lines: &'a [&'a [u8]],
-    x: usize,
-    y: usize,
-}
-
-impl<'a> LowPointsIter<'a> {
-    pub fn new(lines: &'a [&'a [u8]]) -> Self {
-        Self { lines, x: 0, y: 0 }
-    }
-}
-
-impl Iterator for LowPointsIter<'_> {
-    type Item = (usize, usize);
-
-    fn next(&mut self) -> Option<Self::Item> {
-        let lines = self.lines;
-
-        for y in self.y..self.lines.len() {
-            for x in self.x..self.lines[y].len() {
-                if x > 0 && lines[y][x - 1] <= lines[y][x] {
-                    continue;
-                }
-
-                if x + 1 < lines[y].len() && lines[y][x + 1] <= lines[y][x] {
-                    continue;
-                }
-
-                if y > 0 && lines[y - 1][x] <= lines[y][x] {
-                    continue;
-                }
-
-                if y + 1 < lines.len() && lines[y + 1][x] <= lines[y][x] {
-                    continue;
-                }
-
-                self.x = x + 1;
-                self.y = y;
-
-                return Some((x, y));
-            }
-            self.x = 0;
-        }
-
-        self.y = lines.len();
-
-        None
-    }
-}
-
 pub fn part1(input: &mut dyn Read) -> String {
     let mut buffer = Vec::new();
     input.read_to_end(&mut buffer).unwrap();
@@ -60,10 +10,31 @@ pub fn part1(input: &mut dyn Read) -> String {
         .filter(|s| !s.is_empty())
         .collect();
 
-    LowPointsIter::new(&lines)
-        .map(|(x, y)| 1 + (lines[y][x] - b'0') as i32)
-        .sum::<i32>()
-        .to_string()
+    let mut total_danger = 0;
+
+    for y in 0..lines.len() {
+        for x in 0..lines[y].len() {
+            if x > 0 && lines[y][x - 1] <= lines[y][x] {
+                continue;
+            }
+
+            if x + 1 < lines[y].len() && lines[y][x + 1] <= lines[y][x] {
+                continue;
+            }
+
+            if y > 0 && lines[y - 1][x] <= lines[y][x] {
+                continue;
+            }
+
+            if y + 1 < lines.len() && lines[y + 1][x] <= lines[y][x] {
+                continue;
+            }
+
+            total_danger += 1 + (lines[y][x] - b'0') as i32;
+        }
+    }
+
+    total_danger.to_string()
 }
 
 pub fn part2(input: &mut dyn Read) -> String {
@@ -83,41 +54,46 @@ pub fn part2(input: &mut dyn Read) -> String {
 
     let mut sizes = Vec::with_capacity(4);
 
-    for (x, y) in LowPointsIter::new(&lines) {
-        todo.push((x, y));
+    for y in 0..lines.len() {
+        for x in 0..lines[0].len() {
+            if visited[y][x] || lines[y][x] == b'9' {
+                continue;
+            }
 
-        let mut size = 1;
-        visited[y][x] = true;
+            todo.push((x, y));
+            let mut size = 1;
+            visited[y][x] = true;
 
-        while let Some((x, y)) = todo.pop() {
-            let mut add = |x: usize, y: usize| {
-                if lines[y][x] != b'9' && !visited[y][x] {
-                    size += 1;
-                    visited[y][x] = true;
-                    todo.push((x, y));
+            while let Some((x, y)) = todo.pop() {
+                let mut add = |x: usize, y: usize| {
+                    if lines[y][x] != b'9' && !visited[y][x] {
+                        size += 1;
+                        visited[y][x] = true;
+                        todo.push((x, y));
+                    }
+                };
+
+                if x > 0 {
+                    add(x - 1, y);
                 }
-            };
 
-            if x > 0 {
-                add(x - 1, y);
+                if x + 1 < lines[y].len() {
+                    add(x + 1, y);
+                }
+
+                if y > 0 {
+                    add(x, y - 1)
+                }
+
+                if y + 1 < lines.len() {
+                    add(x, y + 1);
+                }
             }
 
-            if x + 1 < lines[y].len() {
-                add(x + 1, y);
-            }
-
-            if y > 0 {
-                add(x, y - 1)
-            }
-
-            if y + 1 < lines.len() {
-                add(x, y + 1);
-            }
+            sizes.push(Reverse(size));
+            sizes.sort_unstable();
+            sizes.truncate(3);
         }
-
-        sizes.push(Reverse(size));
-        sizes.sort_unstable();
-        sizes.truncate(3);
     }
 
     sizes.into_iter().fold(1, |a, Reverse(b)| a * b).to_string()