Day 10-1

src/day_10_1/command.rs

+pub enum Command {
+    NoOp { cycles: u32 },
+    AddX { cycles: u32, value: i32 },
+}
+
+impl Command {
+    pub fn from_str(input: &str) -> Command {
+        match input.split(' ').next().expect("Expected command!") {
+            "noop" => Self::NoOp { cycles: 1 },
+            "addx" => Self::AddX {
+                cycles: 2,
+                value: input
+                    .split(' ')
+                    .nth(1)
+                    .expect("Expected value!")
+                    .parse()
+                    .expect("Expected value to be a number!"),
+            },
+            _ => panic!("Unexpected command!"),
+        }
+    }
+}

src/day_10_1/mod.rs

+mod command;
+
+use command::Command;
+
+pub fn solve_from_str(input: &str) -> i32 {
+    let commands = input
+        .split('\n')
+        .map(|command| Command::from_str(command))
+        .collect();
+
+    solve(&commands)
+}
+
+pub fn solve(commands: &Vec<Command>) -> i32 {
+    let mut cycle = 1;
+    let mut x = 1;
+
+    let mut signal_strengths = Vec::new();
+
+    for command in commands {
+        match command {
+            Command::NoOp { cycles } => {
+                increment_cycle(&mut cycle, &mut signal_strengths, cycles, &x);
+            },
+            Command::AddX { cycles, value } => {
+                increment_cycle(&mut cycle, &mut signal_strengths, cycles, &x);
+
+                x += value;
+            },
+        }
+    }
+
+    signal_strengths.iter().sum()
+}
+
+fn increment_cycle(cycle: &mut u32, signal_strengths: &mut Vec<i32>, cycles: &u32, x: &i32) {
+    for _ in 0..*cycles {
+        if [20, 60, 100, 140, 180, 220].contains(cycle) {
+            signal_strengths.push(*x * *cycle as i32);
+        }
+
+        *cycle += 1;
+    }
+}

src/main.rs

@@ -14,13 +14,14 @@ mod day_8_1;
 mod day_8_2;
 mod day_9_1;
 mod day_9_2;
+mod day_10_1;
 
 use std::fs;
 
 fn main() {
     let input = fs::read_to_string("input").expect("Could not read input!");
 
-    let solution = day_9_2::solve_from_str(input.as_str());
+    let solution = day_10_1::solve_from_str(input.as_str());
 
     println!("Solution: {}", solution);
 }