Dreaded_X/aoc
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Simplified solution

Browse Source
This commit is contained in:
Dreaded_X 2022-12-06 00:47:50 +01:00
parent 381ecb2f85
commit 5554cfedb3
Signed by: Dreaded_X
GPG Key ID: 76BDEC4E165D8AD9
1 changed files with 41 additions and 65 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

106
2022/src/bin/day5.rs
View File

@ -49,7 +49,7 @@ impl fmt::Display for Boat {
for i in 0..self.stacks.len() {
match self.top(i+1) {
Some(cr) => write!(f, "{}", cr.letter)?,
None => panic!("No crate in stack")
None => write!(f, " ")?,
}
}
@ -75,23 +75,26 @@ impl Boat {
}
// Because of how we load the data, each stack is upside down
boat.reverse();
for stack in boat.stacks.iter_mut() {
stack.1.reverse()
}
return boat;
}
fn push(&mut self, index: usize, cr: Crate) {
let stack = self.stacks.entry(index).or_insert(vec![]);
stack.push(cr);
fn take(&mut self, index: usize, amount: usize) -> Vec<Crate> {
let stack = self.stacks.entry(index).or_default();
stack.split_off(stack.len()-amount)
}
fn pop(&mut self, index: usize) -> Option<Crate> {
let stack = match self.stacks.get_mut(&index) {
Some(s) => s,
None => return None,
};
fn put(&mut self, index: usize, mut vec: Vec<Crate>) {
let stack = self.stacks.entry(index).or_default();
stack.append(&mut vec);
}
stack.pop()
fn push(&mut self, index: usize, cr: Crate) {
let stack = self.stacks.entry(index).or_default();
stack.push(cr);
}
fn top(&self, index: usize) -> Option<&Crate> {
@ -102,16 +105,9 @@ impl Boat {
stack.last()
}
fn reverse(&mut self) {
for stack in self.stacks.iter_mut() {
stack.1.reverse()
}
}
}
// -- Helpers --
fn parse_instruction(s: &str) -> (usize, usize, usize) {
lazy_static! {
static ref RE: Regex = Regex::new(r"move (?P<amount>[0-9]+) from (?P<from>[0-9]) to (?P<to>[0-9])").unwrap();
@ -127,6 +123,31 @@ fn parse_instruction(s: &str) -> (usize, usize, usize) {
(amount, from, to)
}
fn solution(input: &str, reverse: bool) -> Output {
// The current layout description ends with an empty line
let mut boat = Boat::new(&input
.lines()
.take_while(|line| !line.is_empty())
.collect());
// Each instruction starts with an 'm'
input
.lines()
.skip_while(|line| !line.starts_with('m'))
.map(parse_instruction)
.for_each(|(amount, from, to)| {
let mut taken = boat.take(from, amount);
// The order needs to be reversed in part due to the crates being moves one at the time
// instead of the whole stack at once as happens in part 2
if reverse {
taken.reverse();
}
boat.put(to, taken);
});
Output::String(boat.to_string())
}
// -- Solution --
pub struct Day;
impl aoc::Solver for Day {
@ -135,55 +156,10 @@ impl aoc::Solver for Day {
}
fn part1(input: &str) -> Output {
// The current layout description ends with an empty line
let mut boat = Boat::new(&input
.lines()
.take_while(|line| !line.is_empty())
.collect());
// Each instruction starts with an 'm'
input
.lines()
.skip_while(|line| !line.starts_with('m'))
.map(parse_instruction)
.for_each(|(amount, from, to)| {
for _ in 0..amount {
let cr = boat.pop(from).unwrap();
boat.push(to, cr);
}
});
Output::String(boat.to_string())
solution(input, true)
}
fn part2(input: &str) -> Output {
// The current layout description ends with an empty line
let mut boat = Boat::new(&input
.lines()
.take_while(|line| !line.is_empty())
.collect());
// Each instruction starts with an 'm'
input
.lines()
.skip_while(|line| !line.starts_with('m'))
.map(parse_instruction)
.for_each(|(amount, from, to)| {
// @TODO Is there a nicer way to do this?
let mut temp = vec![];
for _ in 0..amount {
let cr = boat.pop(from).unwrap();
temp.push(cr);
}
temp.reverse();
for cr in temp {
boat.push(to, cr);
}
});
Output::String(boat.to_string())
solution(input, false)
}
}