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|
use aoc::fetch::fetch;
#[derive(Debug)]
struct Ring {
inner: usize,
counter: usize,
}
impl Ring {
fn new() -> Self {
Self {
inner: 50,
counter: Default::default(),
}
}
const MAX: usize = 99;
fn left(&mut self, num: usize, count_each_step: bool) {
for _ in 0..num {
if self.inner == 0 {
self.inner = Self::MAX;
} else {
self.inner -= 1;
}
if count_each_step {
self.check_counter();
}
}
if !count_each_step {
self.check_counter();
}
}
fn right(&mut self, num: usize, count_each_step: bool) {
for _ in 0..num {
if self.inner == Self::MAX {
self.inner = 0;
} else {
self.inner += 1;
}
if count_each_step {
self.check_counter();
}
}
if !count_each_step {
self.check_counter();
}
}
fn check_counter(&mut self) {
if self.inner == 0 {
self.counter += 1;
}
}
}
fn solve(count_each_step: bool) -> usize {
let mut ring = Ring::new();
let input = fetch(
1, '\n',
);
for i in input {
if i.is_empty() {
continue;
}
let dir = i
.chars()
.next()
.unwrap();
let num = i[1..]
.parse()
.unwrap();
match dir {
'L' => ring.left(
num,
count_each_step,
),
'R' => ring.right(
num,
count_each_step,
),
_ => {}
}
}
ring.counter
}
pub fn part1() -> usize {
solve(false)
}
pub fn part2() -> usize {
solve(true)
}
|
