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#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_mut)]
use num::complex::Complex as c;
use num::Complex;
use std::cmp::min;
use std::collections::HashMap;
use std::fs::File;
use std::io::Read;
type Matrix<T> = Vec<Vec<T>>;
fn rec(
pos: Complex<i32>,
dir: Complex<i32>,
conti: u32,
mut hl: i32,
s: &mut HashMap<(Complex<i32>, Complex<i32>, u32), i32>,
m: &Matrix<i32>,
) -> i32 {
if !(0 <= pos.re && pos.re < m[0].len() as i32 && 0 <= pos.im && pos.im < m.len() as i32) {
return 999999999;
}
hl += m[pos.im as usize][pos.re as usize];
if conti > 3 {
return 999999999;
}
// println!("{}", pos);
if let Some(hl_) = s.get(&(pos, dir, conti)) {
if hl_ <= &hl {
return 999999999;
}
}
s.insert((pos, dir, conti), hl);
if pos == c::new(m[0].len() as i32 - 1, m.len() as i32 - 1) {
return hl;
}
let mut ret = 999999999;
let new_pos = pos + dir;
let new_dir = dir;
ret = min(ret, rec(new_pos, new_dir, conti + 1, hl, s, m));
let new_pos = pos + dir;
let new_dir = dir * c::i();
ret = min(ret, rec(new_pos, new_dir, 0, hl, s, m));
let new_pos = pos + dir;
let new_dir = dir * (-c::i());
ret = min(ret, rec(new_pos, new_dir, 0, hl, s, m));
return ret;
}
fn main() {
let filename = "in/day17.ref";
// let filename = "in/day17.pzl";
let mut f = File::open(filename).expect("cannot open file");
let mut content = String::new();
f.read_to_string(&mut content).expect("cannot read file");
let lines = content.trim_end().split('\n');
// println!("{:?}", lines);
let mut m: Matrix<i32> = Vec::new();
for line in lines {
let mut mr: Vec<i32> = Vec::new();
for c in line.chars() {
mr.push(c.to_digit(10).unwrap() as i32);
}
m.push(mr);
}
// println!("{:?}", m);
let mut state: HashMap<(Complex<i32>, Complex<i32>, u32), i32> = HashMap::new();
let mut pos = c::new(0, 0);
let mut dir = c::new(1, 0);
let res1 = rec(pos, dir, 0, 0, &mut state, &m);
// println!("{:?}", state);
let mut res2 = 0;
println!("res1: {}", res1);
println!("res2: {}", res2);
}
// 612 too low
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