Skip to content

Day 10 by atauveron #131

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
atauveron wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Day 10 by atauveron #131

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 4 additions & 0 deletions Cargo.toml
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -76,3 +76,7 @@ path = "./day-08/part-1/atauveron.rs"
[[bin]]
name = "day-08-part-2-atauveron"
path = "./day-08/part-2/atauveron.rs"

[[bin]]
name = "day-10-part-1-atauveron"
path = "./day-10/part-1/atauveron.rs"
31 changes: 31 additions & 0 deletions day-10/input/atauveron.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,31 @@
#...##.####.#.......#.##..##.#.
#.##.#..#..#...##..##.##.#.....
#..#####.#......#..#....#.###.#
...#.#.#...#..#.....#..#..#.#..
.#.....##..#...#..#.#...##.....
##.....#..........##..#......##
.##..##.#.#....##..##.......#..
#.##.##....###..#...##...##....
##.#.#............##..#...##..#
###..##.###.....#.##...####....
...##..#...##...##..#.#..#...#.
..#.#.##.#.#.#####.#....####.#.
#......###.##....#...#...#...##
.....#...#.#.#.#....#...#......
#..#.#.#..#....#..#...#..#..##.
#.....#..##.....#...###..#..#.#
.....####.#..#...##..#..#..#..#
..#.....#.#........#.#.##..####
.#.....##..#.##.....#...###....
###.###....#..#..#.....#####...
#..##.##..##.#.#....#.#......#.
.#....#.##..#.#.#.......##.....
##.##...#...#....###.#....#....
.....#.######.#.#..#..#.#.....#
.#..#.##.#....#.##..#.#...##..#
.##.###..#..#..#.###...#####.#.
#...#...........#.....#.......#
#....##.#.#..##...#..####...#..
#.####......#####.....#.##..#..
.#...#....#...##..##.#.#......#
#..###.....##.#.......#.##...##
80 changes: 80 additions & 0 deletions day-10/part-1/atauveron.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,80 @@
use std::env::args;
use std::time::Instant;

use std::collections::HashSet;

fn main() {
let now = Instant::now();
let output = run(&args().nth(1).expect("Please provide an input"));
let elapsed = now.elapsed();
println!("_duration:{}", elapsed.as_secs_f64() * 1000.);
println!("{}", output);
}

fn run(input: &str) -> usize {
let mut asteroids: Vec<(isize, isize)> = Vec::new();
let mut x = 0;
for line in input.lines() {
for (y, c) in line.char_indices() {
if c == '#' {
asteroids.push((x, y as isize));
}
}
x += 1;
}
let mut count: Vec<usize> = Vec::new();
for index in 0..asteroids.len() {
count.push(count_visible(index, &asteroids));
}
// Find and return the maximum
let mut max_loc = 0;
for v in count {
if v > max_loc {
max_loc = v;
}
}
max_loc
}

fn count_visible(index: usize, asteroids: &Vec<(isize, isize)>) -> usize {
let (pos_x, pos_y) = asteroids[index];
let mut directions: HashSet<(isize, isize)> = HashSet::new();
for asteroid in asteroids {
if asteroid.0 == pos_x && asteroid.1 == pos_y {
continue;
}
let d_x = asteroid.0 - pos_x;
let d_y = asteroid.1 - pos_y;
let d = gcd(d_x.abs() as usize, d_y.abs() as usize) as isize;
directions.insert((d_x / d, d_y / d));
}
directions.len()
}

fn gcd(first: usize, second: usize) -> usize {
// variable names based off Euclidean division equation: a = b * q + r
let (mut a, mut b) = if first > second {
(first, second)
} else {
(second, first)
};

while b != 0 {
let r = a % b;
a = b;
b = r;
}

a
}

#[cfg(test)]
mod tests {
use super::*;

#[test]
fn run_test() {
let input = "......#.#.\n#..#.#....\n..#######.\n.#.#.###..\n.#..#.....\n..#....#.#\n#..#....#.\n.##.#..###\n##...#..#.\n.#....####\n";
assert_eq!(run(input), 33);
}
}