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www.mikescher.com/www/statics/aoc/2020/14_solution.rs

130 lines
4.0 KiB
Rust

use crate::common::AdventOfCodeDay;
use std::collections::HashMap;
pub struct Day14 {
input: Vec<String>,
}
impl Day14 {
pub fn new() -> Self {
let input_bytes = include_bytes!("../res/14_input.txt");
let input_str = String::from_utf8_lossy(input_bytes);
let lines = input_str
.lines()
.map(|p| String::from(p))
.collect::<Vec<String>>();
Self {
input: lines
}
}
}
impl AdventOfCodeDay for Day14 {
fn task_1(&self) -> String {
let mut mask_set: u64 = 0;
let mut mask_unset: u64 = 0;
let mut mem: HashMap<u64, u64> = HashMap::new();
for line in &self.input {
if line.starts_with("mask = ") {
let strmask = &line[7..];
mask_set = u64::from_str_radix(&strmask.replace("X", "0"), 2).unwrap();
mask_unset = u64::from_str_radix(&strmask.replace("X", "1"), 2).unwrap();
verboseln!("Mask: {} -> set:{} | unset:{}", strmask, mask_set, mask_unset);
} else if line.starts_with("mem[") {
let addr = line.replace("mem[", "").replace("] =", "").split(' ').nth(0).unwrap().parse::<u64>().unwrap();
let value = line.replace("mem[", "").replace("] =", "").split(' ').nth(1).unwrap().parse::<u64>().unwrap();
let masked_val = (value | mask_set) & mask_unset;
mem.insert(addr, masked_val);
verboseln!("Set: {} := {} (orig: {})", addr, masked_val, value);
}
}
return mem.iter().map(|(_,v)| v).sum::<u64>().to_string();
}
fn task_2(&self) -> String {
let mask_36: u64 = 0b111111_111111_111111_111111_111111_111111;
let mut addr: Vec<(u64,u64)> = Vec::with_capacity(1024);
let mut mem: HashMap<u64, u64> = HashMap::new();
for line in &self.input {
if line.starts_with("mask = ") {
let strmask = &line[7..];
let mask_set = u64::from_str_radix(&strmask.replace("X", "0"), 2).unwrap();
let mask_unset = 0u64;
verboseln!("{0} | {0}", strmask);
verboseln!("{:0>36b} | {:0>36b}", mask_set, mask_unset);
verboseln!();
let floats = strmask.chars().rev().enumerate().filter(|(_,v)| *v == 'X').map(|(i,_)| i).collect::<Vec<usize>>();
addr.clear();
for fmask in 0..(2u64.pow(floats.len() as u32)) {
let mut nf_mask_set = mask_set;
let mut nf_mask_unset = mask_unset;
let mut ii = 0;
for i in &floats {
let fbmask = 1u64 << *i;
if fmask & (1<<ii) != 0 {
nf_mask_set = nf_mask_set | fbmask;
} else {
nf_mask_unset = nf_mask_unset | fbmask;
}
ii += 1;
}
addr.push((nf_mask_set, nf_mask_unset));
verboseln!("{:0>36b} | {:0>36b} ( {:0>10b} )", nf_mask_set, nf_mask_unset, fmask);
}
verboseln!();
verboseln!();
} else if line.starts_with("mem[") {
let val_addr = line.replace("mem[", "").replace("] =", "").split(' ').nth(0).unwrap().parse::<u64>().unwrap();
let val_value = line.replace("mem[", "").replace("] =", "").split(' ').nth(1).unwrap().parse::<u64>().unwrap();
for (mset,munset) in &addr {
let masked_addr = ((val_addr | mset) & !munset) & mask_36;
mem.insert(masked_addr, val_value);
}
verboseln!("Write into {} mems", addr.len());
verboseln!();
}
}
return mem.iter().map(|(_,v)| v).sum::<u64>().to_string();
}
}