02-dive

2021/src/bin/01-sonar-sweep.rs

@@ -1,11 +1,8 @@
-#![allow(dead_code, unused_imports)]
 use anyhow::Result;
 use itertools::Itertools;
 
-use std::{io::{stdin, Read}, str::FromStr};
-
 fn descending_window(size: usize) -> Result<usize> {
-    Ok(aoc::read_one_per_line::<u32>("./data/1.depths")?
+    Ok(aoc::read_one_per_line::<u32>("./data/01.depths")?
         .windows(size)
         .filter(|win| win[0] < win[size - 1])
         .collect_vec()

2021/src/bin/02-dive.rs

@@ -0,0 +1,77 @@
+use anyhow::Result;
+
+use std::str::FromStr;
+
+#[derive(Debug)]
+enum Direction {
+    Forward(u64),
+    Down(u64),
+    Up(u64),
+}
+
+impl FromStr for Direction {
+    type Err = anyhow::Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        if let Some((direction, distance)) = s.split_once(" ") {
+            let distance = distance.parse()?;
+
+            Ok(match direction {
+                "forward" => Direction::Forward(distance),
+                "down" => Direction::Down(distance),
+                "up" => Direction::Up(distance),
+                _ => panic!("not a command"),
+            })
+        } else {
+            Err(anyhow::format_err!("could not split direction"))
+        }
+    }
+}
+
+fn part_1() -> Result<u64> {
+    let cmds = aoc::read_one_per_line::<Direction>("./data/02.directions")?;
+    //                    horizontal, depth
+    let loc = cmds.iter().fold((0, 0), |mut loc, dir| match dir {
+        Direction::Forward(dis) => {
+            loc.0 += dis;
+            loc
+        }
+        Direction::Down(dis) => {
+            loc.1 += dis;
+            loc
+        }
+        Direction::Up(dis) => {
+            loc.1 -= dis;
+            loc
+        }
+    });
+    Ok(loc.0 * loc.1)
+}
+
+fn part_2() -> Result<u64> {
+    let cmds = aoc::read_one_per_line::<Direction>("./data/02.directions")?;
+    //                    horizontal, depth, aim
+    let loc = cmds.iter().fold((0, 0, 0), |mut loc, dir| match dir {
+        Direction::Forward(dis) => {
+            loc.0 += dis;
+            loc.1 += dis * loc.2;
+            loc
+        }
+        Direction::Down(dis) => {
+            loc.2 += dis;
+            loc
+        }
+        Direction::Up(dis) => {
+            loc.2 -= dis;
+            loc
+        }
+    });
+    Ok(loc.0 * loc.1)
+}
+
+fn main() -> Result<()> {
+    println!("Part 1: {}", part_1()?);
+    println!("Part 2: {}", part_2()?);
+
+    Ok(())
+}

2021/src/bin/03-binary-diagnostic.rs

@@ -0,0 +1,3 @@
+fn main() -> anyhow::Result<()> {
+    let lines = aoc::read_vec_per_line("./data/03.diagnostics", |c| char::to_digit(c, 2)?);
+}