1 files changed, 90 insertions, 0 deletions
diff --git a/2023/day17.rs b/2023/day17.rs
new file mode 100644
index 0000000..37aff45
--- /dev/null
+++ b/2023/day17.rs
@@ -0,0 +1,90 @@
+#![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