diff --git a/day11/Cargo.lock b/day11/Cargo.lock
new file mode 100644
index 0000000..15649e1
--- /dev/null
+++ b/day11/Cargo.lock
@@ -0,0 +1,137 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
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diff --git a/day11/Cargo.toml b/day11/Cargo.toml
new file mode 100644
index 0000000..6ea2497
--- /dev/null
+++ b/day11/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "day11"
+version = "0.1.0"
+authors = ["Tyler Hallada <tyler@hallada.net>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+num_enum = "0.4.2"
diff --git a/day11/input/input.txt b/day11/input/input.txt
new file mode 100644
index 0000000..2a4e083
--- /dev/null
+++ b/day11/input/input.txt
@@ -0,0 +1 @@
+3,8,1005,8,338,1106,0,11,0,0,0,104,1,104,0,3,8,1002,8,-1,10,1001,10,1,10,4,10,108,1,8,10,4,10,102,1,8,28,1,108,6,10,1,3,7,10,3,8,1002,8,-1,10,1001,10,1,10,4,10,108,1,8,10,4,10,1001,8,0,58,2,5,19,10,1,1008,7,10,2,105,6,10,1,1007,7,10,3,8,1002,8,-1,10,1001,10,1,10,4,10,1008,8,0,10,4,10,101,0,8,97,1006,0,76,1,106,14,10,2,9,9,10,1006,0,74,3,8,102,-1,8,10,101,1,10,10,4,10,108,1,8,10,4,10,1002,8,1,132,1006,0,0,2,1104,15,10,3,8,1002,8,-1,10,1001,10,1,10,4,10,1008,8,0,10,4,10,1001,8,0,162,1,1005,13,10,3,8,1002,8,-1,10,101,1,10,10,4,10,108,1,8,10,4,10,101,0,8,187,1,1,15,10,2,3,9,10,1006,0,54,3,8,102,-1,8,10,101,1,10,10,4,10,108,0,8,10,4,10,102,1,8,220,1,104,5,10,3,8,102,-1,8,10,101,1,10,10,4,10,1008,8,0,10,4,10,102,1,8,247,1,5,1,10,1,1109,2,10,3,8,1002,8,-1,10,101,1,10,10,4,10,1008,8,0,10,4,10,1001,8,0,277,1006,0,18,3,8,1002,8,-1,10,101,1,10,10,4,10,108,1,8,10,4,10,101,0,8,301,2,105,14,10,1,5,1,10,2,1009,6,10,1,3,0,10,101,1,9,9,1007,9,1054,10,1005,10,15,99,109,660,104,0,104,1,21101,0,47677546524,1,21101,0,355,0,1105,1,459,21102,936995299356,1,1,21101,0,366,0,1106,0,459,3,10,104,0,104,1,3,10,104,0,104,0,3,10,104,0,104,1,3,10,104,0,104,1,3,10,104,0,104,0,3,10,104,0,104,1,21101,0,206312807515,1,21102,1,413,0,1105,1,459,21101,206253871296,0,1,21102,424,1,0,1106,0,459,3,10,104,0,104,0,3,10,104,0,104,0,21102,1,709580554600,1,21102,1,447,0,1105,1,459,21101,0,868401967464,1,21101,458,0,0,1106,0,459,99,109,2,22102,1,-1,1,21102,1,40,2,21101,0,490,3,21102,480,1,0,1106,0,523,109,-2,2105,1,0,0,1,0,0,1,109,2,3,10,204,-1,1001,485,486,501,4,0,1001,485,1,485,108,4,485,10,1006,10,517,1101,0,0,485,109,-2,2105,1,0,0,109,4,2101,0,-1,522,1207,-3,0,10,1006,10,540,21102,0,1,-3,21201,-3,0,1,21202,-2,1,2,21101,0,1,3,21101,0,559,0,1105,1,564,109,-4,2106,0,0,109,5,1207,-3,1,10,1006,10,587,2207,-4,-2,10,1006,10,587,21202,-4,1,-4,1105,1,655,21201,-4,0,1,21201,-3,-1,2,21202,-2,2,3,21102,606,1,0,1105,1,564,22102,1,1,-4,21102,1,1,-1,2207,-4,-2,10,1006,10,625,21102,1,0,-1,22202,-2,-1,-2,2107,0,-3,10,1006,10,647,22101,0,-1,1,21101,0,647,0,106,0,522,21202,-2,-1,-2,22201,-4,-2,-4,109,-5,2106,0,0
diff --git a/day11/src/intcode.rs b/day11/src/intcode.rs
new file mode 100644
index 0000000..20fbfa8
--- /dev/null
+++ b/day11/src/intcode.rs
@@ -0,0 +1,461 @@
+use std::collections::HashMap;
+use std::convert::TryFrom;
+use std::error::Error;
+use std::fs::File;
+use std::io::prelude::*;
+use std::result;
+use std::str::FromStr;
+
+use num_enum::TryFromPrimitive;
+
+type Result<T> = result::Result<T, Box<dyn Error>>;
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct Intcode {
+    pub integers: HashMap<usize, i64>,
+    pub pointer: usize,
+    pub halted: bool,
+    pub relative_base: i64,
+}
+
+#[derive(Debug, PartialEq)]
+pub struct Instruction {
+    opcode: Opcode,
+    parameter_modes: Vec<ParameterMode>,
+}
+
+impl TryFrom<i64> for Instruction {
+    type Error = Box<dyn Error>;
+
+    fn try_from(integer: i64) -> Result<Self> {
+        let opcode: Opcode = Opcode::try_from((integer % 100) as u8)?;
+        let modes_integer = integer / 100;
+        let mut parameter_modes = vec![];
+        for parameter_index in 0..opcode.parameter_count() {
+            parameter_modes.push(ParameterMode::try_from(
+                (modes_integer % (10_i64.pow(parameter_index + 1)) / 10_i64.pow(parameter_index))
+                    as u8,
+            )?)
+        }
+        Ok(Instruction {
+            opcode,
+            parameter_modes,
+        })
+    }
+}
+
+#[derive(Debug, PartialEq, TryFromPrimitive)]
+#[repr(u8)]
+pub enum Opcode {
+    Add = 1,
+    Mult = 2,
+    Input = 3,
+    Output = 4,
+    JumpIfTrue = 5,
+    JumpIfFalse = 6,
+    LessThan = 7,
+    Equals = 8,
+    RelativeBaseOffset = 9,
+    Halt = 99,
+}
+
+impl Opcode {
+    pub fn parameter_count(&self) -> u32 {
+        match self {
+            Opcode::Add => 3,
+            Opcode::Mult => 3,
+            Opcode::Input => 1,
+            Opcode::Output => 1,
+            Opcode::JumpIfTrue => 2,
+            Opcode::JumpIfFalse => 2,
+            Opcode::LessThan => 3,
+            Opcode::Equals => 3,
+            Opcode::RelativeBaseOffset => 1,
+            Opcode::Halt => 0,
+        }
+    }
+
+    pub fn target_parameter_index(&self) -> Option<usize> {
+        match self {
+            Opcode::Add => Some(2),
+            Opcode::Mult => Some(2),
+            Opcode::Input => Some(0),
+            Opcode::Output => None,
+            Opcode::JumpIfTrue => None,
+            Opcode::JumpIfFalse => None,
+            Opcode::LessThan => Some(2),
+            Opcode::Equals => Some(2),
+            Opcode::RelativeBaseOffset => None,
+            Opcode::Halt => None,
+        }
+    }
+}
+
+#[derive(Debug, PartialEq, TryFromPrimitive)]
+#[repr(u8)]
+pub enum ParameterMode {
+    Position = 0,
+    Immediate = 1,
+    Relative = 2,
+}
+
+impl FromStr for Intcode {
+    type Err = Box<dyn Error>;
+
+    fn from_str(s: &str) -> Result<Intcode> {
+        let intcode_string = s.trim().to_string();
+        let mut integers = HashMap::new();
+        for (index, code) in intcode_string.split(',').enumerate() {
+            integers.insert(index, code.parse().unwrap());
+        }
+
+        Ok(Intcode::new(integers))
+    }
+}
+
+impl Intcode {
+    fn new(integers: HashMap<usize, i64>) -> Intcode {
+        Intcode {
+            integers,
+            pointer: 0,
+            halted: false,
+            relative_base: 0,
+        }
+    }
+
+    fn load_parameters(&mut self, pointer: usize, instruction: &Instruction) -> Vec<i64> {
+        (0..instruction.opcode.parameter_count() as usize)
+            .map(|parameter_index| {
+                let mut integer = *self
+                    .integers
+                    .entry(pointer + parameter_index + 1)
+                    .or_insert(0);
+                match instruction.parameter_modes[parameter_index] {
+                    ParameterMode::Position => match instruction.opcode.target_parameter_index() {
+                        Some(target_parameter_index)
+                            if target_parameter_index == parameter_index => {}
+                        _ => {
+                            integer = *self.integers.entry(integer as usize).or_insert(0);
+                        }
+                    },
+                    ParameterMode::Relative => match instruction.opcode.target_parameter_index() {
+                        Some(target_parameter_index)
+                            if target_parameter_index == parameter_index =>
+                        {
+                            integer += self.relative_base;
+                        }
+                        _ => {
+                            integer = *self
+                                .integers
+                                .entry((self.relative_base + integer) as usize)
+                                .or_insert(0);
+                        }
+                    },
+                    _ => {}
+                }
+                integer
+            })
+            .collect()
+    }
+
+    pub fn execute(&mut self, inputs: &[i64]) -> Result<Vec<i64>> {
+        let mut input_index = 0;
+        let mut output = vec![];
+
+        loop {
+            let instruction =
+                Instruction::try_from(*self.integers.entry(self.pointer).or_insert(0))?;
+            let parameters = self.load_parameters(self.pointer, &instruction);
+            let mut jump_pointer: Option<usize> = None;
+
+            match instruction.opcode {
+                Opcode::Add => {
+                    self.integers
+                        .insert(parameters[2] as usize, parameters[0] + parameters[1]);
+                }
+                Opcode::Mult => {
+                    self.integers
+                        .insert(parameters[2] as usize, parameters[0] * parameters[1]);
+                }
+                Opcode::Input => {
+                    if input_index >= inputs.len() {
+                        break; // pause execution to wait for more input
+                    }
+                    self.integers
+                        .insert(parameters[0] as usize, inputs[input_index]);
+                    input_index += 1;
+                }
+                Opcode::Output => {
+                    output.push(parameters[0]);
+                }
+                Opcode::JumpIfTrue => {
+                    if parameters[0] != 0 {
+                        jump_pointer = Some(parameters[1] as usize);
+                    }
+                }
+                Opcode::JumpIfFalse => {
+                    if parameters[0] == 0 {
+                        jump_pointer = Some(parameters[1] as usize);
+                    }
+                }
+                Opcode::LessThan => {
+                    if parameters[0] < parameters[1] {
+                        self.integers.insert(parameters[2] as usize, 1);
+                    } else {
+                        self.integers.insert(parameters[2] as usize, 0);
+                    }
+                }
+                Opcode::Equals => {
+                    if parameters[0] == parameters[1] {
+                        self.integers.insert(parameters[2] as usize, 1);
+                    } else {
+                        self.integers.insert(parameters[2] as usize, 0);
+                    }
+                }
+                Opcode::RelativeBaseOffset => {
+                    self.relative_base += parameters[0];
+                }
+                Opcode::Halt => {
+                    self.halted = true;
+                    break;
+                }
+            }
+
+            match jump_pointer {
+                Some(jump_pointer) => self.pointer = jump_pointer,
+                None => self.pointer += 1 + instruction.opcode.parameter_count() as usize,
+            }
+        }
+
+        Ok(output)
+    }
+}
+
+pub fn read_intcode(filename: &str) -> Result<Intcode> {
+    let mut file = File::open(filename)?;
+    let mut intcode_string = String::new();
+    file.read_to_string(&mut intcode_string)?;
+
+    Ok(intcode_string.parse()?)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const TEST_INPUT: &str = "input/test1.txt";
+
+    #[test]
+    fn reads_intcode() {
+        assert_eq!(
+            read_intcode(TEST_INPUT).unwrap(),
+            Intcode::new(
+                vec![3, 15, 3, 16, 1002, 16, 10, 16, 1, 16, 15, 15, 4, 15, 99, 0, 0]
+                    .into_iter()
+                    .enumerate()
+                    .collect()
+            ),
+        );
+    }
+
+    #[test]
+    fn converts_integer_to_instruction() {
+        assert_eq!(
+            Instruction::try_from(1002).unwrap(),
+            Instruction {
+                opcode: Opcode::Mult,
+                parameter_modes: vec![
+                    ParameterMode::Position,
+                    ParameterMode::Immediate,
+                    ParameterMode::Position
+                ],
+            }
+        );
+
+        assert_eq!(
+            Instruction::try_from(101).unwrap(),
+            Instruction {
+                opcode: Opcode::Add,
+                parameter_modes: vec![
+                    ParameterMode::Immediate,
+                    ParameterMode::Position,
+                    ParameterMode::Position
+                ],
+            }
+        );
+    }
+
+    #[test]
+    fn executes_intcodes() {
+        let mut intcode = Intcode::new(vec![1, 0, 0, 0, 99].into_iter().enumerate().collect());
+        intcode.execute(&[0]).unwrap();
+        assert_eq!(
+            intcode.integers,
+            vec![2, 0, 0, 0, 99].into_iter().enumerate().collect()
+        );
+
+        let mut intcode = Intcode::new(vec![2, 3, 0, 3, 99].into_iter().enumerate().collect());
+        intcode.execute(&[0]).unwrap();
+        assert_eq!(
+            intcode.integers,
+            vec![2, 3, 0, 6, 99].into_iter().enumerate().collect()
+        );
+
+        let mut intcode = Intcode::new(vec![2, 4, 4, 5, 99, 0].into_iter().enumerate().collect());
+        intcode.execute(&[0]).unwrap();
+        assert_eq!(
+            intcode.integers,
+            vec![2, 4, 4, 5, 99, 9801].into_iter().enumerate().collect()
+        );
+
+        let mut intcode = Intcode::new(
+            vec![1, 1, 1, 4, 99, 5, 6, 0, 99]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        intcode.execute(&[0]).unwrap();
+        assert_eq!(
+            intcode.integers,
+            vec![30, 1, 1, 4, 2, 5, 6, 0, 99]
+                .into_iter()
+                .enumerate()
+                .collect()
+        );
+
+        let mut intcode = Intcode::new(
+            vec![1, 9, 10, 3, 2, 3, 11, 0, 99, 30, 40, 50]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        intcode.execute(&[0]).unwrap();
+        assert_eq!(
+            intcode.integers,
+            vec![3500, 9, 10, 70, 2, 3, 11, 0, 99, 30, 40, 50]
+                .into_iter()
+                .enumerate()
+                .collect()
+        );
+    }
+
+    #[test]
+    fn less_and_equal_outputs() {
+        let intcode = Intcode::new(
+            vec![3, 9, 8, 9, 10, 9, 4, 9, 99, -1, 8]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[8]).unwrap(), vec![1]);
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![0]);
+
+        let intcode = Intcode::new(
+            vec![3, 9, 7, 9, 10, 9, 4, 9, 99, -1, 8]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![1]);
+        assert_eq!(intcode.clone().execute(&[9]).unwrap(), vec![0]);
+
+        let intcode = Intcode::new(
+            vec![3, 3, 1108, -1, 8, 3, 4, 3, 99]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[8]).unwrap(), vec![1]);
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![0]);
+
+        let intcode = Intcode::new(
+            vec![3, 3, 1107, -1, 8, 3, 4, 3, 99]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![1]);
+        assert_eq!(intcode.clone().execute(&[9]).unwrap(), vec![0]);
+    }
+
+    #[test]
+    fn jump_outputs() {
+        let intcode = Intcode::new(
+            vec![3, 12, 6, 12, 15, 1, 13, 14, 13, 4, 13, 99, -1, 0, 1, 9]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![0]);
+        assert_eq!(intcode.clone().execute(&[1]).unwrap(), vec![1]);
+
+        let intcode = Intcode::new(
+            vec![3, 3, 1105, -1, 9, 1101, 0, 0, 12, 4, 12, 99, 1]
+                .into_iter()
+                .enumerate()
+                .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![0]);
+        assert_eq!(intcode.clone().execute(&[1]).unwrap(), vec![1]);
+    }
+
+    #[test]
+    fn larger_part2_intcode() {
+        let intcode = Intcode::new(
+            vec![
+                3, 21, 1008, 21, 8, 20, 1005, 20, 22, 107, 8, 21, 20, 1006, 20, 31, 1106, 0, 36,
+                98, 0, 0, 1002, 21, 125, 20, 4, 20, 1105, 1, 46, 104, 999, 1105, 1, 46, 1101, 1000,
+                1, 20, 4, 20, 1105, 1, 46, 98, 99,
+            ]
+            .into_iter()
+            .enumerate()
+            .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[0]).unwrap(), vec![999]);
+        assert_eq!(intcode.clone().execute(&[8]).unwrap(), vec![1000]);
+        assert_eq!(intcode.clone().execute(&[9]).unwrap(), vec![1001]);
+    }
+
+    #[test]
+    fn multiple_input_intcode() {
+        let intcode = Intcode::new(
+            vec![
+                3, 15, 3, 16, 1002, 16, 10, 16, 1, 16, 15, 15, 4, 15, 99, 0, 0,
+            ]
+            .into_iter()
+            .enumerate()
+            .collect(),
+        );
+        assert_eq!(intcode.clone().execute(&[1, 1]).unwrap(), vec![11]);
+    }
+
+    #[test]
+    fn relative_base_offset_quine() {
+        let code = vec![
+            109, 1, 204, -1, 1001, 100, 1, 100, 1008, 100, 16, 101, 1006, 101, 0, 99,
+        ];
+        let intcode = Intcode::new(code.clone().into_iter().enumerate().collect());
+        assert_eq!(intcode.clone().execute(&[]).unwrap(), code);
+    }
+
+    #[test]
+    fn sixteen_digit_output() {
+        let code = vec![1102, 34915192, 34915192, 7, 4, 7, 99, 0];
+        let intcode = Intcode::new(code.into_iter().enumerate().collect());
+        assert_eq!(intcode.clone().execute(&[]).unwrap(), [1219070632396864]);
+    }
+
+    #[test]
+    fn large_output() {
+        let code = vec![104, 1125899906842624, 99];
+        let intcode = Intcode::new(code.into_iter().enumerate().collect());
+        assert_eq!(intcode.clone().execute(&[]).unwrap(), [1125899906842624]);
+    }
+
+    #[test]
+    fn relative_target_parameters() {
+        let code = vec![109, 1, 203, 2, 204, 2, 99];
+        let intcode = Intcode::new(code.into_iter().enumerate().collect());
+        assert_eq!(intcode.clone().execute(&[123]).unwrap(), [123]);
+    }
+}
diff --git a/day11/src/main.rs b/day11/src/main.rs
new file mode 100644
index 0000000..f332091
--- /dev/null
+++ b/day11/src/main.rs
@@ -0,0 +1,189 @@
+use std::collections::HashMap;
+use std::convert::TryFrom;
+use std::error::Error;
+use std::fmt;
+use std::result;
+
+use num_enum::TryFromPrimitive;
+
+mod intcode;
+
+use intcode::{read_intcode, Intcode};
+
+const INPUT: &str = "input/input.txt";
+
+type Result<T> = result::Result<T, Box<dyn Error>>;
+
+#[derive(TryFromPrimitive, Clone, Copy)]
+#[repr(u8)]
+enum Color {
+    Black = 0,
+    White = 1,
+}
+
+#[derive(TryFromPrimitive, Clone, Copy)]
+#[repr(u8)]
+enum Turn {
+    Left = 0,
+    Right = 1,
+}
+
+#[derive(TryFromPrimitive, Clone, Copy)]
+#[repr(u8)]
+enum Direction {
+    Left = 0,
+    Right = 1,
+    Up = 2,
+    Down = 3,
+}
+
+impl Direction {
+    fn turn(&self, turn: Turn) -> Direction {
+        match turn {
+            Turn::Left => match self {
+                Direction::Left => Direction::Down,
+                Direction::Right => Direction::Up,
+                Direction::Up => Direction::Left,
+                Direction::Down => Direction::Right,
+            },
+            Turn::Right => match self {
+                Direction::Left => Direction::Up,
+                Direction::Right => Direction::Down,
+                Direction::Up => Direction::Right,
+                Direction::Down => Direction::Left,
+            },
+        }
+    }
+}
+
+#[derive(PartialEq, Eq, Hash, Clone, Copy)]
+struct Coordinate {
+    x: i64,
+    y: i64,
+}
+
+struct Robot {
+    intcode: Intcode,
+    position: Coordinate,
+    direction: Direction,
+}
+
+impl Robot {
+    fn new(intcode: Intcode) -> Robot {
+        Robot {
+            intcode: intcode.clone(),
+            position: Coordinate { x: 0, y: 0 },
+            direction: Direction::Up,
+        }
+    }
+
+    fn turn_and_move(&mut self, turn: Turn) {
+        self.direction = self.direction.turn(turn);
+        match self.direction {
+            Direction::Left => self.position.x -= 1,
+            Direction::Right => self.position.x += 1,
+            Direction::Up => self.position.y -= 1,
+            Direction::Down => self.position.y += 1,
+        }
+    }
+}
+
+struct Hull {
+    panels: HashMap<Coordinate, Color>,
+}
+
+impl Hull {
+    fn new() -> Hull {
+        Hull {
+            panels: HashMap::new(),
+        }
+    }
+
+    fn paint_registration(&mut self, intcode: Intcode, start_color: Color) -> Result<()> {
+        let mut robot = Robot::new(intcode);
+        let mut current_panel = start_color;
+        while !robot.intcode.halted {
+            let output = robot
+                .intcode
+                .execute(&[current_panel as i64])
+                .expect("Failed to execute intcode");
+            let color = Color::try_from(output[0] as u8)?;
+            let turn = Turn::try_from(output[1] as u8)?;
+
+            self.panels.insert(robot.position, color);
+            robot.turn_and_move(turn);
+            current_panel = *self.panels.get(&robot.position).unwrap_or(&Color::Black);
+        }
+        Ok(())
+    }
+}
+
+impl fmt::Display for Hull {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let start_coord = Coordinate { x: 0, y: 0 };
+        let up_left_corner = Coordinate {
+            x: self
+                .panels
+                .keys()
+                .min_by_key(|coord| coord.x)
+                .unwrap_or(&start_coord)
+                .x,
+            y: self
+                .panels
+                .keys()
+                .min_by_key(|coord| coord.y)
+                .unwrap_or(&start_coord)
+                .y,
+        };
+        let down_right_corner = Coordinate {
+            x: self
+                .panels
+                .keys()
+                .max_by_key(|coord| coord.x)
+                .unwrap_or(&start_coord)
+                .x,
+            y: self
+                .panels
+                .keys()
+                .max_by_key(|coord| coord.y)
+                .unwrap_or(&start_coord)
+                .y,
+        };
+        for y in up_left_corner.y..=down_right_corner.y {
+            let mut row_string = String::new();
+            for x in up_left_corner.x..=down_right_corner.x {
+                row_string += match self
+                    .panels
+                    .get(&Coordinate { x, y })
+                    .unwrap_or(&Color::Black)
+                {
+                    Color::Black => ".",
+                    Color::White => "#",
+                };
+            }
+            write!(f, "{}\n", row_string)?;
+        }
+        Ok(())
+    }
+}
+
+fn solve_part1() -> Result<usize> {
+    let intcode = read_intcode(INPUT)?;
+    let mut hull = Hull::new();
+    hull.paint_registration(intcode, Color::Black)?;
+    Ok(hull.panels.len())
+}
+
+fn solve_part2() -> Result<String> {
+    let intcode = read_intcode(INPUT)?;
+    let mut hull = Hull::new();
+    hull.paint_registration(intcode, Color::White)?;
+    Ok(format!("\n{}", hull))
+}
+
+fn main() -> Result<()> {
+    println!("Part 1: {}", solve_part1()?);
+    println!("Part 2: {}", solve_part2()?);
+
+    Ok(())
+}