mplement 2023 day 14 part 1

2023/src/day14.rs

@@ -1,7 +1,39 @@
-pub fn part1(_input: &[u8]) -> anyhow::Result<String> {
-    anyhow::bail!("Not implemented")
+use crate::common::Grid;
+
+pub fn part1(input: &[u8]) -> anyhow::Result<String> {
+    let grid = Grid::new(input)?;
+    let mut stack_heights = vec![0; grid.width()];
+    let mut load = 0;
+    let height = grid.height();
+
+    for (y, row) in grid.rows().enumerate() {
+        for (&c, stack_height) in row.iter().zip(&mut stack_heights) {
+            match c {
+                b'#' => *stack_height = y + 1,
+                b'O' => {
+                    load += height - *stack_height;
+                    *stack_height += 1;
+                }
+                _ => continue,
+            }
+        }
+    }
+
+    Ok(load.to_string())
 }
 
 pub fn part2(_input: &[u8]) -> anyhow::Result<String> {
     anyhow::bail!("Not implemented")
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const SAMPLE: &[u8] = include_bytes!("samples/14.txt");
+
+    #[test]
+    fn sample_part1() {
+        assert_eq!("136", part1(SAMPLE).unwrap());
+    }
+}