Day 2

5 files changed, 1095 insertions, 0 deletions

diff --git a/02/Cargo.toml b/02/Cargo.toml
new file mode 100644
index 0000000..6c152d7
--- /dev/null
+++ b/02/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "day-02"
+version = "0.1.0"
+authors = ["Gard Spreemann <gspr@nonempty.org>"]
+edition = "2018"
+
+[[bin]]
+name = "part-1"
+path = "src/part-1.rs"
+
+[[bin]]
+name = "part-2"
+path = "src/part-2.rs"
+
+[dependencies]
diff --git a/02/input.txt b/02/input.txt
new file mode 100644
index 0000000..d61291a
--- /dev/null
+++ b/02/input.txt
@@ -0,0 +1,1000 @@
+forward 2
+down 9
+up 6
+forward 1
+down 5
+down 7
+down 9
+forward 9
+down 8
+up 7
+forward 2
+up 6
+forward 4
+down 5
+down 9
+up 1
+down 9
+forward 8
+forward 6
+forward 6
+forward 5
+forward 9
+up 3
+up 5
+forward 1
+down 4
+down 7
+forward 2
+up 3
+down 8
+forward 1
+down 2
+forward 3
+up 1
+up 1
+up 7
+forward 5
+up 8
+forward 8
+forward 8
+down 6
+forward 1
+forward 5
+forward 4
+forward 6
+forward 5
+down 6
+down 9
+forward 9
+down 8
+forward 6
+down 5
+forward 9
+up 3
+up 1
+down 8
+down 7
+down 9
+forward 7
+down 8
+down 9
+down 5
+down 3
+forward 1
+forward 6
+down 1
+forward 9
+down 5
+forward 7
+up 2
+down 8
+forward 1
+down 4
+down 9
+down 4
+up 5
+forward 4
+forward 6
+forward 1
+down 3
+forward 1
+down 6
+up 5
+up 4
+forward 6
+forward 1
+forward 1
+down 2
+up 4
+up 3
+up 2
+up 6
+down 6
+forward 1
+down 8
+forward 1
+up 6
+forward 7
+down 5
+forward 4
+forward 6
+down 4
+forward 4
+down 4
+down 4
+forward 2
+forward 8
+down 5
+down 1
+down 8
+up 5
+up 8
+down 5
+forward 4
+down 6
+up 7
+forward 2
+down 3
+forward 2
+forward 2
+down 9
+down 3
+up 6
+forward 8
+up 2
+up 9
+forward 4
+down 1
+down 5
+forward 4
+down 2
+down 3
+forward 5
+down 4
+forward 7
+up 4
+forward 6
+up 8
+forward 1
+up 9
+down 4
+forward 2
+down 1
+forward 7
+down 3
+down 2
+forward 5
+down 3
+down 9
+down 9
+up 5
+forward 2
+down 8
+up 9
+forward 4
+down 3
+forward 3
+forward 6
+up 2
+forward 3
+down 1
+down 1
+down 1
+forward 7
+forward 4
+forward 7
+down 5
+down 6
+down 2
+forward 6
+down 3
+up 6
+forward 4
+down 8
+up 1
+forward 8
+down 2
+down 5
+forward 4
+down 9
+forward 2
+forward 2
+down 3
+forward 3
+down 1
+forward 2
+down 7
+forward 3
+forward 9
+up 9
+forward 6
+forward 2
+down 1
+down 5
+forward 6
+forward 6
+down 3
+up 3
+forward 9
+down 7
+down 2
+down 4
+down 7
+forward 5
+up 4
+forward 8
+down 5
+forward 7
+down 7
+up 7
+down 8
+forward 9
+up 5
+forward 1
+down 2
+forward 5
+down 9
+forward 3
+down 5
+forward 8
+forward 3
+up 5
+down 2
+up 3
+forward 2
+up 1
+up 5
+down 8
+forward 2
+down 5
+up 4
+up 5
+up 2
+forward 9
+forward 6
+down 9
+up 9
+forward 6
+forward 4
+forward 3
+forward 7
+up 1
+down 2
+down 6
+down 1
+forward 8
+down 1
+forward 6
+down 8
+forward 8
+down 7
+down 6
+down 5
+forward 2
+up 8
+up 6
+up 5
+down 1
+forward 1
+down 1
+down 5
+forward 7
+forward 3
+down 1
+forward 5
+forward 5
+forward 8
+down 1
+up 2
+down 6
+up 6
+forward 6
+forward 6
+down 3
+forward 9
+up 4
+forward 4
+down 6
+up 1
+forward 6
+down 2
+down 5
+down 2
+down 6
+up 5
+down 1
+down 1
+forward 3
+forward 7
+forward 3
+up 2
+down 8
+down 4
+down 1
+down 5
+down 1
+down 9
+forward 6
+down 6
+down 4
+down 6
+down 8
+forward 4
+down 6
+down 7
+forward 8
+down 4
+up 4
+down 1
+forward 1
+forward 4
+forward 1
+up 9
+down 7
+forward 7
+down 4
+forward 1
+up 4
+forward 4
+down 5
+down 7
+forward 5
+forward 7
+forward 1
+forward 1
+forward 9
+forward 9
+up 3
+forward 4
+down 2
+forward 9
+up 8
+forward 3
+up 5
+down 3
+down 8
+forward 8
+down 6
+forward 1
+down 6
+down 6
+up 9
+down 2
+forward 8
+up 9
+down 7
+up 9
+up 8
+up 1
+forward 6
+forward 9
+down 2
+forward 8
+down 1
+up 4
+forward 4
+forward 7
+up 2
+forward 4
+down 5
+forward 3
+down 2
+down 7
+down 4
+down 2
+up 5
+down 5
+down 5
+down 4
+up 1
+forward 7
+down 6
+forward 5
+forward 1
+down 4
+up 9
+down 5
+forward 7
+forward 5
+down 6
+down 3
+down 9
+down 1
+forward 6
+up 2
+down 7
+down 3
+down 6
+up 3
+down 4
+down 4
+forward 9
+down 3
+forward 2
+down 9
+down 8
+up 4
+down 2
+forward 2
+down 5
+down 4
+down 4
+down 2
+forward 6
+down 3
+forward 1
+down 4
+forward 7
+down 5
+up 4
+down 6
+forward 8
+down 6
+forward 2
+forward 4
+forward 5
+forward 7
+forward 4
+forward 5
+down 8
+down 7
+forward 3
+forward 5
+up 7
+forward 1
+down 4
+forward 5
+forward 4
+forward 4
+down 5
+down 8
+forward 8
+down 1
+down 1
+down 5
+up 5
+forward 6
+down 6
+forward 3
+forward 4
+forward 7
+forward 4
+down 8
+forward 2
+down 4
+forward 4
+down 1
+up 2
+forward 6
+up 1
+down 7
+down 9
+forward 7
+forward 2
+up 3
+down 2
+down 9
+down 5
+up 7
+forward 1
+forward 8
+down 8
+up 3
+down 3
+forward 9
+up 4
+down 5
+up 5
+down 1
+up 8
+forward 9
+down 3
+up 6
+forward 6
+forward 1
+down 1
+forward 9
+down 8
+forward 8
+down 6
+up 9
+down 4
+up 3
+up 9
+forward 2
+down 2
+down 2
+forward 3
+down 2
+forward 5
+forward 4
+up 8
+forward 9
+up 7
+forward 2
+down 5
+down 6
+forward 8
+up 7
+forward 4
+forward 3
+up 5
+down 8
+forward 3
+up 2
+down 3
+forward 6
+down 9
+down 2
+down 6
+down 2
+forward 7
+forward 5
+forward 7
+down 8
+forward 2
+down 2
+forward 8
+up 8
+forward 4
+forward 3
+up 5
+down 3
+forward 3
+up 8
+up 7
+down 4
+down 1
+forward 2
+down 1
+up 6
+up 4
+down 3
+up 1
+forward 7
+forward 7
+forward 7
+forward 8
+down 1
+forward 5
+down 6
+forward 9
+forward 7
+forward 7
+down 4
+up 4
+down 6
+down 9
+up 4
+up 2
+up 6
+forward 4
+up 4
+up 6
+down 2
+forward 4
+down 9
+forward 9
+forward 9
+down 1
+forward 7
+down 2
+down 7
+down 8
+down 8
+down 9
+up 9
+down 5
+forward 5
+forward 7
+forward 4
+down 7
+forward 8
+forward 1
+down 8
+up 9
+down 7
+forward 9
+forward 4
+forward 8
+down 9
+forward 4
+down 3
+forward 3
+down 1
+down 1
+down 2
+up 5
+down 2
+down 1
+down 8
+forward 3
+up 2
+forward 7
+down 3
+down 8
+down 1
+forward 4
+forward 7
+down 5
+forward 6
+down 6
+down 2
+forward 6
+down 3
+up 4
+down 7
+forward 7
+up 1
+up 9
+down 1
+down 2
+down 8
+down 7
+up 1
+forward 7
+down 2
+forward 4
+forward 6
+forward 9
+down 6
+forward 2
+up 8
+down 2
+up 2
+up 5
+down 8
+up 6
+down 9
+forward 6
+down 8
+down 6
+down 1
+up 7
+up 6
+down 8
+forward 2
+up 7
+forward 5
+forward 7
+forward 7
+up 5
+forward 2
+down 9
+up 2
+up 8
+up 2
+down 3
+down 7
+forward 9
+down 3
+up 9
+forward 8
+up 8
+forward 4
+forward 8
+forward 6
+up 1
+down 3
+up 1
+down 1
+forward 2
+forward 1
+forward 4
+forward 7
+up 8
+down 9
+up 2
+down 7
+forward 4
+down 3
+forward 4
+forward 2
+down 9
+forward 8
+forward 5
+forward 3
+down 6
+forward 4
+forward 4
+forward 9
+forward 4
+up 5
+down 7
+up 6
+forward 5
+down 5
+forward 4
+down 5
+forward 7
+forward 3
+forward 5
+down 5
+forward 4
+down 5
+up 4
+down 8
+up 3
+down 3
+up 5
+forward 4
+forward 5
+down 6
+forward 6
+forward 1
+forward 8
+down 6
+down 9
+up 5
+forward 2
+forward 8
+up 6
+down 6
+forward 2
+down 8
+forward 7
+forward 7
+down 5
+forward 5
+forward 8
+forward 1
+down 4
+down 2
+down 5
+up 4
+forward 3
+forward 5
+down 4
+down 7
+down 4
+up 9
+up 6
+forward 1
+down 8
+up 8
+up 9
+forward 2
+forward 1
+down 6
+forward 6
+down 4
+forward 7
+up 2
+up 1
+forward 4
+down 1
+forward 8
+forward 3
+up 7
+up 5
+down 1
+forward 8
+forward 6
+up 6
+forward 9
+down 5
+down 9
+forward 2
+down 3
+up 1
+up 7
+down 1
+forward 8
+up 9
+down 1
+down 5
+down 7
+down 5
+down 5
+down 5
+up 9
+forward 9
+forward 7
+forward 4
+forward 6
+down 5
+down 3
+forward 9
+forward 1
+down 1
+down 8
+up 4
+down 9
+forward 9
+up 1
+down 5
+forward 8
+up 6
+forward 3
+down 6
+up 8
+down 7
+forward 3
+forward 6
+down 7
+forward 6
+forward 4
+forward 4
+down 4
+forward 6
+forward 5
+down 6
+forward 6
+down 7
+forward 6
+forward 3
+up 4
+up 2
+up 6
+down 2
+down 8
+forward 5
+forward 1
+up 4
+forward 7
+forward 9
+up 6
+down 7
+down 3
+up 5
+forward 5
+down 8
+up 1
+down 1
+down 3
+down 2
+down 1
+forward 5
+down 3
+down 5
+forward 7
+forward 9
+down 3
+forward 7
+forward 5
+forward 4
+forward 2
+forward 7
+forward 8
+forward 6
+down 8
+forward 5
+forward 6
+forward 6
+down 8
+down 2
+forward 4
+down 7
+forward 6
+down 7
+down 4
+forward 6
+up 6
+forward 4
+forward 9
+forward 2
+forward 3
+forward 1
+down 8
+down 3
+forward 4
+up 3
+forward 7
+forward 1
+down 7
+down 8
+forward 1
+up 8
+forward 8
+up 8
+down 5
+forward 6
+down 8
+down 4
+down 9
+up 1
+down 3
+forward 6
+down 6
+forward 7
+forward 3
+down 6
+down 6
+forward 4
+down 4
+down 1
+down 8
+forward 2
+forward 8
+forward 8
+down 6
+forward 9
+down 9
+down 5
+down 5
+forward 7
+down 1
+forward 1
+down 1
+down 6
+down 1
+forward 1
+up 6
+up 9
+forward 5
+down 6
+forward 8
+forward 6
+down 7
+forward 1
+forward 4
+forward 9
+forward 2
+forward 4
+down 2
+forward 1
+forward 8
+down 1
+down 1
+forward 4
+down 5
+down 3
+down 9
+down 2
+up 8
+down 7
+down 1
+down 9
+forward 2
+forward 2
+up 3
+forward 3
+down 3
+forward 5
+forward 9
+down 7
+up 7
+down 9
+forward 3
+forward 7
+down 1
+forward 8
+down 8
+forward 1
+down 8
+down 6
+forward 2
+down 3
+down 1
+down 8
+forward 3
+up 5
+down 7
+up 2
+up 8
+forward 5
+up 7
+down 6
+up 7
+down 9
+forward 5
+up 4
+forward 9
+down 5
+up 7
+down 2
+up 2
+up 7
+forward 5
+down 6
+forward 4
+down 4
+down 3
+forward 2
+up 2
+down 5
+forward 8
+down 3
+up 7
+down 1
+down 7
+forward 7
+forward 4
+forward 7
+down 2
+down 9
+down 6
+down 9
+down 2
+down 9
+down 7
+down 5
+forward 4
+up 5
+up 7
+forward 2
+forward 7
+down 3
+down 3
+forward 4
diff --git a/02/src/part-1.rs b/02/src/part-1.rs
new file mode 100644
index 0000000..df74f8b
--- /dev/null
+++ b/02/src/part-1.rs
@@ -0,0 +1,34 @@
+use std::io::{BufRead};
+
+#[derive(Debug)]
+enum Command { Down(u64), Forward(u64), Up(u64) }
+
+pub fn main() {
+    let mut stdin = std::io::stdin();
+    let mut handle = stdin.lock();
+
+    let mut depth: u64 = 0;
+    let mut pos: u64 = 0;
+
+    for line in handle.lines() {
+        let l = line.expect("IO error");
+        let mut words = l.split_whitespace();
+        let command_string = words.next().expect("Malformed input");
+        let value_string = words.next().expect("Malformed input");
+        let command: Command = match command_string {
+            "down" => Command::Down(value_string.parse().expect("Malformed input")),
+            "forward" => Command::Forward(value_string.parse().expect("Malformed input")),
+            "up" => Command::Up(value_string.parse().expect("Malformed input")),
+            _ => panic!("Malformed input")
+        };
+
+        match command {
+            Command::Down(x) => depth += x,
+            Command::Forward(x) => pos += x,
+            Command::Up(x) => depth -= x
+        }
+    }
+
+    //println!("Depth: {}. Horizontal position: {}.", depth, pos);
+    println!("{}", depth*pos);
+}
diff --git a/02/src/part-2.rs b/02/src/part-2.rs
new file mode 100644
index 0000000..7d9d86a
--- /dev/null
+++ b/02/src/part-2.rs
@@ -0,0 +1,40 @@
+use std::io::{BufRead};
+
+// It is unclear whether aim can be negative in part 2, so
+// switching everything to signed arithmetic.
+#[derive(Debug)]
+enum Command { Down(i64), Forward(i64), Up(i64) }
+
+pub fn main() {
+    let mut stdin = std::io::stdin();
+    let mut handle = stdin.lock();
+
+    let mut depth: i64 = 0;
+    let mut pos: i64 = 0;
+    let mut aim: i64 = 0;
+
+    for line in handle.lines() {
+        let l = line.expect("IO error");
+        let mut words = l.split_whitespace();
+        let command_string = words.next().expect("Malformed input");
+        let value_string = words.next().expect("Malformed input");
+        let command: Command = match command_string {
+            "down" => Command::Down(value_string.parse().expect("Malformed input")),
+            "forward" => Command::Forward(value_string.parse().expect("Malformed input")),
+            "up" => Command::Up(value_string.parse().expect("Malformed input")),
+            _ => panic!("Malformed input")
+        };
+
+        match command {
+            Command::Down(x) => aim += x,
+            Command::Forward(x) => {
+                pos += x;
+                depth += aim*x;
+            },           
+            Command::Up(x) => aim -= x
+        }
+    }
+
+    //println!("Depth: {}. Horizontal position: {}.", depth, pos);
+    println!("{}", depth*pos);
+}
diff --git a/02/test.txt b/02/test.txt
new file mode 100644
index 0000000..b7172ac
--- /dev/null
+++ b/02/test.txt
@@ -0,0 +1,6 @@
+forward 5
+down 5
+forward 8
+up 3
+down 8
+forward 2