day10 part 1

src/tasks/day10.rs

@@ -0,0 +1,95 @@
+use crate::utils;
+use regex::Regex;
+
+pub fn task1() {
+    let input = utils::read_file("input/day10.txt");
+    // position=<-4,  3> velocity=< 2,  0>
+    let regex = Regex::new(
+        r"position=<\s*(?P<x>-?\d+),\s*(?P<y>-?\d+)> velocity=<\s*(?P<vx>-?\d+),\s*(?P<vy>-?\d+)>",
+    )
+    .unwrap();
+    let mut lights: Vec<Light> = input
+        .lines()
+        //.inspect(|line| println!("{}", line))
+        .map(|line| {
+            let cap = regex.captures(line).unwrap();
+            Light {
+                x: cap["x"].parse::<i32>().unwrap(),
+                y: cap["y"].parse::<i32>().unwrap(),
+                vx: cap["vx"].parse::<i32>().unwrap(),
+                vy: cap["vy"].parse::<i32>().unwrap(),
+            }
+        })
+        .collect();
+
+    // for light in lights.iter() {
+    //     println!("{:?}", light);
+    // }
+
+    let mut old_area = get_area(&lights);
+    loop {
+        let new_lights = lights.iter().map(|light| light.move_copy()).collect();
+        // print_lights(&new_lights);
+        let new_area = get_area(&new_lights);
+        // println!("Area: {} ", new_area);
+        if new_area > old_area {
+            println!("Found a minimum..");
+            print_lights(&lights);
+            break;
+        } else {
+            lights = new_lights;
+            old_area = new_area;
+        }
+    }
+}
+
+fn get_area(lights: &Vec<Light>) -> usize {
+    let xmin = lights.iter().map(|it| it.x).min().unwrap();
+    let xmax = lights.iter().map(|it| it.x).max().unwrap();
+    let ymin = lights.iter().map(|it| it.y).min().unwrap();
+    let ymax = lights.iter().map(|it| it.y).max().unwrap();
+    (xmax - xmin) as usize * (ymax - ymin) as usize
+}
+
+fn print_lights(lights: &Vec<Light>) {
+    let xmin = lights.iter().map(|it| it.x).min().unwrap();
+    let xmax = lights.iter().map(|it| it.x).max().unwrap();
+    let ymin = lights.iter().map(|it| it.y).min().unwrap();
+    let ymax = lights.iter().map(|it| it.y).max().unwrap();
+    let width = xmax - xmin + 1;
+    let height = ymax - ymin + 1;
+
+    let mut screen: Vec<Vec<u8>> = Vec::with_capacity(height as usize);
+    for _ in 0..=height {
+        let mut chars = Vec::with_capacity(width as usize);
+        for _ in 0..=width {
+            chars.push('.' as u8);
+        }
+        screen.push(chars);
+    }
+    lights
+        .iter()
+        .for_each(|light| screen[(light.y - ymin) as usize][(light.x - xmin) as usize] = '#' as u8);
+    for line in screen.iter() {
+        println!("{}", String::from_utf8(line.clone()).unwrap());
+    }
+}
+
+#[derive(Debug)]
+struct Light {
+    x: i32,
+    y: i32,
+    vx: i32,
+    vy: i32,
+}
+
+impl Light {
+    fn move_copy(&self) -> Self {
+        Light {
+            x: self.x + self.vx,
+            y: self.y + self.vy,
+            vx: self.vx,
+            vy: self.vy,
+        }
+    }
+}

src/tasks/mod.rs

@@ -7,3 +7,4 @@ pub mod day06;
 pub mod day07;
 pub mod day08;
 pub mod day09;
+pub mod day10;