Implement day 23.

Could use some optimization, but it works.

2016/src/day23.rs

@@ -0,0 +1,49 @@
+use std::io;
+use common;
+
+#[derive(Default)]
+pub struct Day23 {
+    cpu: common::AssemBunnyCPU,
+}
+
+impl Day23 {
+    pub fn new() -> Day23 {
+        Default::default()
+    }
+}
+
+impl common::Solution for Day23 {
+
+    fn part1(&mut self, input: &mut io::Read) -> String {
+        self.cpu.read_instructions(input);
+        self.cpu.registers[0] = 7;
+        format!("{}", self.cpu.run())
+    }
+
+    fn part2(&mut self, input: &mut io::Read) -> String {
+        self.cpu.read_instructions(input);
+        self.cpu.registers[0] = 12;
+        format!("{}", self.cpu.run())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use common::Solution;
+
+    const SAMPLE_INPUT: &str = "cpy 2 a
+tgl a
+tgl a
+tgl a
+cpy 1 a
+dec a
+dec a";
+
+    #[test]
+    fn sample_part1() {
+        let mut instance = Day23::new();
+        assert_eq!("3", instance.part1(&mut SAMPLE_INPUT.as_bytes()))
+    }
+
+}