1 files changed, 71 insertions, 0 deletions
diff --git a/src/bin/day02.rs b/src/bin/day02.rs
new file mode 100644
index 0000000..c5a7f11
--- /dev/null
+++ b/src/bin/day02.rs
@@ -0,0 +1,71 @@
+use std::io::{self, Read};
+
+#[derive(Debug, Clone, Copy)]
+enum Keypad {
+    K1, K2, K3,
+    K4, K5, K6,
+    K7, K8, K9,
+}
+
+impl Keypad {
+    fn up(self) -> Self {
+        use Keypad::*;
+        match self {
+            K4 => K1, K5 => K2, K6 => K3,
+            K7 => K4, K8 => K5, K9 => K6,
+            _ => self,
+        }
+    }
+
+    fn down(self) -> Self {
+        use Keypad::*;
+        match self {
+            K1 => K4, K2 => K5, K3 => K6,
+            K4 => K7, K5 => K8, K6 => K9,
+            _ => self,
+        }
+    }
+
+    fn left(self) -> Self {
+        use Keypad::*;
+        match self {
+            K2 => K1, K3 => K2,
+            K5 => K4, K6 => K5,
+            K8 => K7, K9 => K8,
+            _ => self,
+        }
+    }
+
+    fn right(self) -> Self {
+        use Keypad::*;
+        match self {
+            K1 => K2, K2 => K3,
+            K4 => K5, K5 => K6,
+            K7 => K8, K8 => K9,
+            _ => self,
+        }
+    }
+}
+
+fn main() {
+    let mut input = String::new();
+    io::stdin().read_to_string(&mut input).unwrap();
+
+    let mut code = Vec::new();
+    let mut key = Keypad::K5;
+
+    for line in input.lines() {
+        for direction in line.chars() {
+            key = match direction {
+                'U' => key.up(),
+                'D' => key.down(),
+                'L' => key.left(),
+                'R' => key.right(),
+                _ => panic!("{} is not a direction", direction),
+            }
+        }
+        code.push(key);
+    }
+
+    println!("Part 1: {:?}", code);
+}