···

       
3
       
3
       
 
       
fn generations(times: u32, mut world: Vec<u8>, size: usize, stuck: bool) -> Vec<u8> {

     

       
4
       
4
       
 
       
    #[inline]

     

       
5
       
5
       
 
       
    fn pos(x: usize, y: usize, size: usize) -> usize {

     

       
6
       
6
       
-
       
        // this shit is unreadable man

     

       
7
       
7
       
-
       
        (1 + y) * (size + 2) + (1 + x)

     

       
6
       
6
       
+
       
        y * (size + 2) + x

     

       
8
       
7
       
 
       
    }

     

       
9
       
8
       
 
       


     

       
10
       
9
       
 
       
    #[inline]

     
···

       
13
       
12
       
 
       
        unsafe { *world.get_unchecked(pos(x, y, size)) }

     

       
14
       
13
       
 
       
    }

     

       
15
       
14
       
 
       


     

       
16
       
16
       
-
       
    let sizem = size - 1;

     

       
15
       
15
       
+
       
    let sizep = size + 1;

     

       
17
       
16
       
 
       


     

       
18
       
17
       
 
       
    let mut new_world = vec![0_u8; (size + 2).pow(2)];

     

       
19
       
18
       
 
       


     

       
20
       
19
       
 
       
    if stuck {

     

       
21
       
21
       
-
       
        world[pos(0, 0, size)] = 1;

     

       
22
       
22
       
-
       
        world[pos(sizem, 0, size)] = 1;

     

       
23
       
23
       
-
       
        world[pos(0, sizem, size)] = 1;

     

       
24
       
24
       
-
       
        world[pos(sizem, sizem, size)] = 1;

     

       
20
       
20
       
+
       
        world[pos(1, 1, size)] = 1;

     

       
21
       
21
       
+
       
        world[pos(size, 1, size)] = 1;

     

       
22
       
22
       
+
       
        world[pos(1, size, size)] = 1;

     

       
23
       
23
       
+
       
        world[pos(size, size, size)] = 1;

     

       
25
       
24
       
 
       
    }

     

       
26
       
25
       
 
       


     

       
27
       
26
       
 
       
    for _ in 0..times {

     

       
28
       
28
       
-
       
        for yo in 0..size {

     

       
27
       
27
       
+
       
        for yo in 1..sizep {

     

       
29
       
28
       
 
       
            let ym = yo - 1;

     

       
30
       
29
       
 
       
            let yp = yo + 1;

     

       
31
       
31
       
-
       
            for xo in 0..size {

     

       
30
       
30
       
+
       
            for xo in 1..sizep {

     

       
32
       
31
       
 
       
                let xm = xo - 1;

     

       
33
       
32
       
 
       
                let xp = xo + 1;

     

       
34
       
33
       
 
       


     
···

       
49
       
48
       
 
       


     

       
50
       
49
       
 
       
        // i hate the duplication here :(

     

       
51
       
50
       
 
       
        if stuck {

     

       
52
       
52
       
-
       
            world[pos(0, 0, size)] = 1;

     

       
53
       
53
       
-
       
            world[pos(sizem, 0, size)] = 1;

     

       
54
       
54
       
-
       
            world[pos(0, sizem, size)] = 1;

     

       
55
       
55
       
-
       
            world[pos(sizem, sizem, size)] = 1;

     

       
51
       
51
       
+
       
            world[pos(1, 1, size)] = 1;

     

       
52
       
52
       
+
       
            world[pos(size, 1, size)] = 1;

     

       
53
       
53
       
+
       
            world[pos(1, size, size)] = 1;

     

       
54
       
54
       
+
       
            world[pos(size, size, size)] = 1;

     

       
56
       
55
       
 
       
        }

     

       
57
       
56
       
 
       
    }

     

       
58
       
57
       
 
       
    world

     
···

       
61
       
60
       
 
       
fn main() {

     

       
62
       
61
       
 
       
    let input = include_str!("../../input.txt").trim();

     

       
63
       
62
       
 
       
    let size = input.split_once("\n").expect("invalid input").0.len();

     

       
64
       
64
       
-
       
    // reads the input but adds a line of buffer on the sides. unreadable

     

       
63
       
63
       
+
       
    // reads the input but adds a line of buffer on the sides

     

       
65
       
64
       
 
       
    let buffer_line = ".".repeat(size);

     

       
66
       
65
       
 
       
    let input: Vec<u8> = format!("{buffer_line}\n{input}\n{buffer_line}")

     

       
67
       
66
       
 
       
        .split("\n")