advent-of-code/2018/16/src/main.rs

111 lines
3.8 KiB
Rust

#[macro_use] extern crate text_io;
use std::collections::HashMap;
mod functions;
use crate::functions::*;
struct Call {
before: [usize; 4],
call: [usize; 4],
after: [usize; 4],
}
impl Call {
pub fn new() -> Self {
Call {
before: [0, 0, 0, 0],
call: [0, 0, 0, 0],
after: [0, 0, 0, 0],
}
}
}
fn check(func: &fn(usize, usize, usize, &[usize; 4]) -> [usize; 4], call: &Call) -> bool {
return func(call.call[1], call.call[2], call.call[3], &call.before) == call.after;
}
fn verify_fn(func: &fn(usize, usize, usize, &[usize; 4]) -> [usize; 4], calls: &Vec<&Call>) -> bool {
for call in calls {
if !check(&func, &call) {
return false;
}
}
return true;
}
fn part1(calls: &Vec<Call>, fns: &[fn(usize, usize, usize, &[usize; 4]) -> [usize; 4]; 16]) {
let mut more_than_three = 0;
for call in calls {
let mut correct = 0;
for func in fns.iter() {
if check(&func, &call) {
correct += 1;
}
}
if correct >= 3 {
more_than_three += 1;
}
}
println!("{}", more_than_three);
}
fn get_mapping(calls: &Vec<Call>, fns: &[fn(usize, usize, usize, &[usize; 4]) -> [usize; 4]; 16])
-> HashMap<usize, fn(usize, usize, usize, &[usize; 4]) -> [usize; 4]> {
let mut mapping: HashMap<usize, fn(usize, usize, usize, &[usize; 4]) -> [usize; 4]> = HashMap::new();
let mut funcs = fns.into_iter().enumerate().collect::<Vec<_>>();
while funcs.len() > 0 {
for i in 0..16 {
let op_calls = calls.iter().filter(|&c| c.call[0] == i).collect::<Vec<_>>();
let valid = funcs.iter().filter(|&f| verify_fn(&f.1, &op_calls)).collect::<Vec<_>>();
if valid.len() == 1 {
let (found_id, found) = *valid.get(0).unwrap();
mapping.insert(i, *found.clone());
let index = funcs.iter().position(|f| f.0 == *found_id).unwrap();
funcs.remove(index);
}
}
}
return mapping;
}
fn num_string_to_array(input: &str) -> [usize; 4] {
let mut out: [usize; 4] = [0, 0, 0, 0];
scan!(input.bytes() => "{} {} {} {}", out[0], out[1], out[2], out[3]);
return out;
}
fn main() {
let fns = [addi, addr, muli, mulr, seti, setr, bani, banr, bori, borr, gtir, gtri, gtrr, eqir, eqri, eqrr];
// Apparently, this needs to be mutable for me to take elements inside the loop later
let mut lines = include_str!("../input").lines().filter(|line| line != &"").peekable();
let mut calls: Vec<Call> = Vec::new();
while lines.peek() != None {
let mut call = Call::new();
scan!(lines.next().unwrap().bytes() => "Before: [{}, {}, {}, {}]", call.before[0], call.before[1], call.before[2], call.before[3]);
call.call = num_string_to_array(lines.next().unwrap());
scan!(lines.next().unwrap().bytes() => "After: [{}, {}, {}, {}]", call.after[0], call.after[1], call.after[2], call.after[3]);
calls.push(call);
}
part1(&calls, &fns);
// Part 2
let program_lines = include_str!("../input2").lines();
let mapping = get_mapping(&calls, &fns);
println!("garbage ends");
let mut registers: [usize; 4] = [0, 0, 0, 0];
//scan!(program_lines.next().unwrap().bytes() => "{} {} {} {}", registers[0], registers[1], registers[2], registers[3]);
for line in program_lines {
let call = num_string_to_array(line);
registers = mapping.get(&call[0]).unwrap()(call[1], call[2], call[3], &registers);
println!("regs: {}, {}, {}, {}", registers[0], registers[1], registers[2], registers[3]);
println!("call: {}, {}, {}, {}", call[0], call[1], call[2], call[3]);
}
// 464 is too low
println!("{}", registers[0]);
}