124 lines
3.2 KiB
Rust
124 lines
3.2 KiB
Rust
use crate::prelude::*;
|
|
|
|
mod operation;
|
|
|
|
use operation::*;
|
|
|
|
pub fn solution() -> Solution {
|
|
Solution::new(Day::new(14, 2020), part_1, part_2)
|
|
.with_expected(9967721333886_i64, 4355897790573_i64)
|
|
}
|
|
|
|
fn part_1(input: &str) -> Result<String> {
|
|
let operations = input.lines().map(Into::into).collect::<Vec<Operation>>();
|
|
|
|
let mut current_mask = "".to_string();
|
|
let mut memory = HashMap::new();
|
|
|
|
for operation in operations {
|
|
match operation {
|
|
Operation::SetMask(mask) => current_mask = mask.clone(),
|
|
Operation::SetMemory(address, mut value) => {
|
|
for (index, character) in current_mask.chars().rev().enumerate() {
|
|
match character {
|
|
'0' => value &= !(1 << index),
|
|
'1' => value |= 1 << index,
|
|
_ => (),
|
|
}
|
|
}
|
|
|
|
*memory.entry(address).or_insert(value) = value;
|
|
}
|
|
}
|
|
}
|
|
|
|
Ok(
|
|
memory
|
|
.iter()
|
|
.map(|(_, value)| value)
|
|
.sum::<i64>()
|
|
.to_string(),
|
|
)
|
|
}
|
|
|
|
fn part_2(input: &str) -> Result<String> {
|
|
let operations = input.lines().map(Into::into).collect::<Vec<Operation>>();
|
|
|
|
let mut current_mask = "".to_string();
|
|
let mut memory = HashMap::new();
|
|
|
|
for operation in operations {
|
|
match operation {
|
|
Operation::SetMask(mask) => current_mask = mask.clone(),
|
|
Operation::SetMemory(mut address, value) => {
|
|
for (index, character) in current_mask.chars().rev().enumerate() {
|
|
if character == '1' {
|
|
address |= 1 << index;
|
|
}
|
|
}
|
|
|
|
let mut new_mask = String::new();
|
|
for (index, character) in format!("{:036b}", address).char_indices() {
|
|
if current_mask.chars().nth(index) == Some('X') {
|
|
new_mask += "X";
|
|
} else {
|
|
new_mask += &character.to_string();
|
|
}
|
|
}
|
|
|
|
let mut floating_addresses = HashSet::new();
|
|
floating_addresses.insert(new_mask);
|
|
while floating_addresses
|
|
.iter()
|
|
.any(|address| address.contains('X'))
|
|
{
|
|
for address in floating_addresses.clone() {
|
|
for new_address in combine(address.clone()) {
|
|
floating_addresses.insert(new_address);
|
|
}
|
|
|
|
floating_addresses.remove(&address);
|
|
}
|
|
}
|
|
|
|
let floating_addresses = floating_addresses
|
|
.iter()
|
|
.map(|address| i64::from_str_radix(address, 2).unwrap())
|
|
.collect::<Vec<i64>>();
|
|
for mut address in floating_addresses {
|
|
for (index, character) in current_mask.chars().rev().enumerate() {
|
|
if character == '1' {
|
|
address |= 1 << index;
|
|
}
|
|
}
|
|
|
|
*memory.entry(address).or_insert(value) = value;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
Ok(
|
|
memory
|
|
.iter()
|
|
.map(|(_, value)| *value)
|
|
.sum::<i64>()
|
|
.to_string(),
|
|
)
|
|
}
|
|
|
|
fn combine(input: String) -> Vec<String> {
|
|
let mut result = vec![];
|
|
|
|
for (index, character) in input.char_indices() {
|
|
if character == 'X' {
|
|
let zero = format!("{}{}{}", &input[0..index], '0', &input[index + 1..]);
|
|
result.push(zero);
|
|
let one = format!("{}{}{}", &input[0..index], '1', &input[index + 1..]);
|
|
result.push(one);
|
|
}
|
|
}
|
|
|
|
result
|
|
}
|