Added day 11

src/days/day11.rs

@@ -0,0 +1,97 @@
+use std::{path::Path, str::FromStr, collections::HashSet, ops::Div, cmp::{min, max}};
+
+use itertools::Itertools;
+use num::Integer;
+
+use crate::{error::AdventError, input::read_into};
+
+struct Chart {
+    stride: usize,
+    space: Vec<char>,
+    empty_rows: HashSet<usize>,
+    empty_columns: HashSet<usize>
+}
+
+impl FromStr for Chart {
+    type Err = AdventError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let stride = s.lines().next().ok_or(AdventError("No first line".into()))?.len();
+        Ok(Chart {
+            stride,
+            space: s.chars().filter(|c| !c.is_ascii_whitespace()).collect_vec(),
+            empty_rows: HashSet::<usize>::new(),
+            empty_columns: HashSet::<usize>::new(),
+        })
+    }
+}
+
+impl Chart {
+    fn detect_doubles(&mut self) {
+        for x in 0..self.stride {
+            if self.space.iter().skip(x).step_by(self.stride).all(|c| *c == '.') {
+                self.empty_columns.insert(x);
+            }
+        }
+        for y in 0..self.space.len().div(self.stride) {
+            if self.space.iter().skip(y*self.stride).take(self.stride).all(|c| *c == '.') {
+                self.empty_rows.insert(y);
+            }
+        }
+    }
+
+    fn find_galaxys(&self) -> Vec<(usize, usize)> {
+        let mut vec = vec![];
+        for (i, c) in self.space.iter().enumerate() {
+            if *c == '#' {
+                let x = i.div_mod_floor(&self.stride);
+                vec.push((x.1, x.0));
+            }
+        }
+        vec
+    }
+
+    fn distance(&self, c1: &(usize, usize), c2: &(usize, usize), extra_distance: u64) -> u64 {
+        let mut steps = 0;
+        for x in (min(c1.0, c2.0)..=max(c1.0, c2.0)).into_iter().skip(1) {
+            steps += 1;
+            if self.empty_columns.contains(&x) {
+                steps += extra_distance;
+            }
+        }
+        for y in (min(c1.1, c2.1)..=max(c1.1, c2.1)).into_iter().skip(1) {
+            steps += 1;
+            if (self.empty_rows).contains(&y) {
+                steps += extra_distance;
+            }
+        }
+        steps
+    }
+}
+
+pub fn one() -> Result<u64, AdventError> {
+    let mut chart = read_into::<Chart>(Path::new("resources/input11.txt"))?;
+    chart.detect_doubles();
+    let galaxy_coords = chart.find_galaxys();
+    let mut sum: u64 = 0;
+    for (i, c1) in galaxy_coords.iter().enumerate() {
+        for c2 in galaxy_coords.iter().skip(i+1) {
+            sum += chart.distance(c1, c2, 2-1);
+        }
+    }
+    Ok(sum as u64)
+}
+
+
+pub fn two() -> Result<u64, AdventError> {
+    let mut chart = read_into::<Chart>(Path::new("resources/input11.txt"))?;
+    chart.detect_doubles();
+    let galaxy_coords = chart.find_galaxys();
+    let mut sum: u64 = 0;
+    for (i, c1) in galaxy_coords.iter().enumerate() {
+        for c2 in galaxy_coords.iter().skip(i+1) {
+            sum += chart.distance(c1, c2, 1000000-1); 
+        }
+    }
+    Ok(sum as u64)
+}

src/days/mod.rs

@@ -7,4 +7,5 @@ pub mod day6;
 pub mod day7;
 pub mod day8;
 pub mod day9;
-pub mod day10;
+pub mod day10;
+pub mod day11;

src/main.rs

@@ -21,6 +21,7 @@ fn main() -> Result<(), AdventError> {
         (day8::one as fn() -> Result<u64, AdventError>, day8::two as fn() -> Result<u64, AdventError>),
         (day9::one as fn() -> Result<u64, AdventError>, day9::two as fn() -> Result<u64, AdventError>),
         (day10::one as fn() -> Result<u64, AdventError>, day10::two as fn() -> Result<u64, AdventError>),
+        (day11::one as fn() -> Result<u64, AdventError>, day11::two as fn() -> Result<u64, AdventError>),
     ];
 
     if env::args().len() == 1 {