diff --git a/day10/src/main.rs b/day10/src/main.rs
index 5841013..b27b258 100644
--- a/day10/src/main.rs
+++ b/day10/src/main.rs
@@ -1,5 +1,80 @@
+use std::collections::HashMap;
+
+#[derive(Debug)]
+enum Instruction {
+    Addx(isize),
+    Noop,
+}
+use Instruction::*;
+
+impl Instruction {
+    pub fn from_line(line: &str) -> Self {
+        let parts: Vec<&str> = line.split_ascii_whitespace().collect();
+
+        if parts.len() == 2 && parts[0] == "addx" {
+            let value = parts[1].parse::<isize>().unwrap();
+
+            return Addx(value);
+        }
+
+        Noop
+    }
+}
+
+// -----------------------------------------------------------------------------
+
+#[derive(Debug)]
+struct CPU {
+    x: isize,
+}
+
+impl CPU {
+    pub fn new() -> Self {
+        CPU { x: 1 }
+    }
+
+    fn noop(&self) -> (usize, Option<isize>) {
+        (1, None)
+    }
+
+    fn addx(&mut self, i: isize) -> (usize, Option<isize>) {
+        self.x += i;
+
+        (2, Some(self.x))
+    }
+
+    pub fn run(&mut self, command: Instruction) -> (usize, Option<isize>) {
+        match command {
+            Addx(i) => self.addx(i),
+            Noop => self.noop(),
+        }
+    }
+}
+
+// -----------------------------------------------------------------------------
+
+#[derive(Debug)]
+struct CycleCounter {
+    cpu: CPU,
+    log: HashMap<usize, isize>,
+    cycle: usize,
+}
+
+impl CycleCounter {
+    pub fn new() -> Self {
+        Self {
+            cpu: CPU::new(),
+            log: HashMap::new(),
+            cycle: 1,
+        }
+    }
+}
+
+// -----------------------------------------------------------------------------
+
 fn main() {
     let file_str = include_str!("input.txt");
+    let instructions: Vec<Instruction> = file_str.lines().map(Instruction::from_line).collect();
 }
 
 #[cfg(test)]