advent-of-code-2021/day13/src/main.rs
Louis Vallat 5293bf274e
Added day 13 code for part 1 and 2
Signed-off-by: Louis Vallat <louis@louis-vallat.xyz>
2021-12-19 00:49:30 +01:00

72 lines
2.1 KiB
Rust

use std::{fs, env, collections::HashSet};
fn read_input(path: &str) -> String {
return fs::read_to_string(path).expect("Cannot read file.");
}
fn parse_input(s: &str) -> (HashSet<(i32, i32)>, Vec<(char, i32)>) {
let mut is_fold = false;
let mut t = HashSet::new();
let mut i = vec![];
for l in s.lines() {
if l == "" { is_fold = true; continue; }
if !is_fold {
let x = l.split_once(",").unwrap();
t.insert((x.0.parse().unwrap(), x.1.parse().unwrap()));
} else {
let x = l.split_once("=").unwrap();
i.push((x.0.chars().last().unwrap(), x.1.parse().unwrap()));
}
}
return (t, i);
}
fn apply_n_folds(i: &HashSet<(i32, i32)>, f: &Vec<(char, i32)>, n: usize) -> HashSet<(i32, i32)> {
let mut h = i.clone();
for x in 0..n {
for c in h.clone().iter() {
if f[x].0 == 'y' {
h.insert((c.0, if c.1 > f[x].1 { c.1 - (c.1 - f[x].1) * 2 } else { c.1 }));
if c.1 > f[x].1 {
h.remove(c);
}
} else {
h.insert((if c.0 > f[x].1 { c.0 - (c.0 - f[x].1) * 2 } else { c.0 }, c.1));
if c.0 > f[x].1 {
h.remove(c);
}
}
}
}
return h;
}
fn show_array(i: &HashSet<(i32, i32)>) {
let m = i.iter().map(|e| e.0).max().unwrap();
let n = i.iter().map(|e| e.1).max().unwrap();
for y in 0..=n {
print!("\t\t");
for x in 0..=m {
if i.contains(&(x, y)) {
print!("{}", '#');
} else {
print!(" ");
}
}
println!();
}
}
fn main() {
let args: Vec<String> = env::args().collect();
for arg in args.iter().skip(1) {
let input = read_input(&arg);
let vec_in = parse_input(&input);
println!("[{}]", &arg);
println!("\t[Part 1] => Answer is '{}'.", apply_n_folds(&vec_in.0, &vec_in.1, 1).len());
println!("\t[Part 2] => Answer is:");
show_array(&apply_n_folds(&vec_in.0, &vec_in.1, vec_in.1.len()));
}
}