···

       
1
       
 
       
use std::mem::swap;

     

       
2
       
 
       


     

       
3
       
-
       
fn generations(mut world: Vec<u8>, size: usize, part_2: bool) -> u32 {

     

       
4
       
 
       
    let pos = |x, y| y * (size + 2) + x;

     

       
5
       
 
       


     

       
6
       
 
       
    let sizep = size + 1;

     

       
7
       
 
       


     

       
8
       
-
       
    let mut new_world = vec![0_u8; (size + 2).pow(2)];

     

       
9
       
 
       


     

       
10
       
 
       
    let mut rolls = 0;

     

       
11
       
 
       


     
···

       
18
       
 
       
                let xp = xo + 1;

     

       
19
       
 
       


     

       
20
       
 
       
                unsafe {

     

       
21
       
-
       
                    let was = *world.get_unchecked(pos(xo, yo)) == 1;

     

       
22
       
-
       
                    let neighbours = world.get_unchecked(pos(xm, ym))

     

       
23
       
-
       
                        + world.get_unchecked(pos(xo, ym))

     

       
24
       
-
       
                        + world.get_unchecked(pos(xp, ym))

     

       
25
       
-
       
                        + world.get_unchecked(pos(xm, yo))

     

       
26
       
-
       
                        + world.get_unchecked(pos(xp, yo))

     

       
27
       
-
       
                        + world.get_unchecked(pos(xm, yp))

     

       
28
       
-
       
                        + world.get_unchecked(pos(xo, yp))

     

       
29
       
-
       
                        + world.get_unchecked(pos(xp, yp));

     

       
30
       
-
       
                    *new_world.get_unchecked_mut(pos(xo, yo)) =

     

       
31
       
 
       
                        match (was, neighbours < 4) {

     

       
32
       
 
       
                            (true, true) => {

     

       
33
       
 
       
                                rolls += 1;

     
···

       
40
       
 
       
            }

     

       
41
       
 
       
        }

     

       
42
       
 
       


     

       
43
       
-
       
        if !part_2 || world == new_world {

     

       
44
       
 
       
            break;

     

       
45
       
 
       
        }

     

       
46
       
 
       


     

       
47
       
-
       
        swap(&mut world, &mut new_world);

     

       
48
       
 
       
    }

     

       
49
       
 
       
    rolls

     

       
50
       
 
       
}

     
···

       
65
       
 
       
        .flatten()

     

       
66
       
 
       
        .collect();

     

       
67
       
 
       


     

       
68
       
-
       
    let part_1 = generations(input.clone(), size, false);

     

       
69
       
 
       
    println!("Part 1: {}", part_1);

     

       
70
       
 
       


     

       
71
       
-
       
    let part_2 = generations(input.clone(), size, true);

     

       
72
       
 
       
    println!("Part 2: {}", part_2);

     

       
73
       
 
       
}

     

···

       
1
       
 
       
use std::mem::swap;

     

       
2
       
 
       


     

       
3
       
+
       
fn solve(mut warehouse: Vec<u8>, size: usize, part_2: bool) -> u32 {

     

       
4
       
 
       
    let pos = |x, y| y * (size + 2) + x;

     

       
5
       
 
       


     

       
6
       
 
       
    let sizep = size + 1;

     

       
7
       
 
       


     

       
8
       
+
       
    let mut new_warehouse = vec![0_u8; (size + 2).pow(2)];

     

       
9
       
 
       


     

       
10
       
 
       
    let mut rolls = 0;

     

       
11
       
 
       


     
···

       
18
       
 
       
                let xp = xo + 1;

     

       
19
       
 
       


     

       
20
       
 
       
                unsafe {

     

       
21
       
+
       
                    let was = *warehouse.get_unchecked(pos(xo, yo)) == 1;

     

       
22
       
+
       
                    let neighbours = warehouse.get_unchecked(pos(xm, ym))

     

       
23
       
+
       
                        + warehouse.get_unchecked(pos(xo, ym))

     

       
24
       
+
       
                        + warehouse.get_unchecked(pos(xp, ym))

     

       
25
       
+
       
                        + warehouse.get_unchecked(pos(xm, yo))

     

       
26
       
+
       
                        + warehouse.get_unchecked(pos(xp, yo))

     

       
27
       
+
       
                        + warehouse.get_unchecked(pos(xm, yp))

     

       
28
       
+
       
                        + warehouse.get_unchecked(pos(xo, yp))

     

       
29
       
+
       
                        + warehouse.get_unchecked(pos(xp, yp));

     

       
30
       
+
       
                    *new_warehouse.get_unchecked_mut(pos(xo, yo)) =

     

       
31
       
 
       
                        match (was, neighbours < 4) {

     

       
32
       
 
       
                            (true, true) => {

     

       
33
       
 
       
                                rolls += 1;

     
···

       
40
       
 
       
            }

     

       
41
       
 
       
        }

     

       
42
       
 
       


     

       
43
       
+
       
        if !part_2 || warehouse == new_warehouse {

     

       
44
       
 
       
            break;

     

       
45
       
 
       
        }

     

       
46
       
 
       


     

       
47
       
+
       
        swap(&mut warehouse, &mut new_warehouse);

     

       
48
       
 
       
    }

     

       
49
       
 
       
    rolls

     

       
50
       
 
       
}

     
···

       
65
       
 
       
        .flatten()

     

       
66
       
 
       
        .collect();

     

       
67
       
 
       


     

       
68
       
+
       
    let part_1 = solve(input.clone(), size, false);

     

       
69
       
 
       
    println!("Part 1: {}", part_1);

     

       
70
       
 
       


     

       
71
       
+
       
    let part_2 = solve(input.clone(), size, true);

     

       
72
       
 
       
    println!("Part 2: {}", part_2);

     

       
73
       
 
       
}