[2024/18] p1 & p2 solved

Author: StarlitGhost

.aoc_tiles/tiles/2024/18.png

@@ -0,0 +1,25 @@
+5,4
+4,2
+4,5
+3,0
+2,1
+6,3
+2,4
+1,5
+0,6
+3,3
+2,6
+5,1
+1,2
+5,5
+2,5
+6,5
+1,4
+0,4
+6,4
+1,1
+6,1
+1,0
+0,5
+1,6
+2,0

2024/18/example

@@ -0,0 +1,51 @@
+from GhostyUtils import aoc
+from GhostyUtils.grid import Grid
+from GhostyUtils.vec2 import Vec2, Dir
+from GhostyUtils.pathfinding import a_star, reconstruct_path
+from functools import partial
+
+
+aoc.argparser.add_argument("-s", "--size", type=int, default=71, help="size of 2d memory")
+aoc.argparser.add_argument("-b", "--bytes", type=int, default=1024, help="number of bytes to drop")
+
+
+def neighbours(pos: tuple, grid: Grid) -> list[tuple]:
+    return list(cell for cell in grid.neighbours(pos, diagonal=False)
+                if grid[cell] != '#')
+
+
+def main():
+    inputs = aoc.read_lines()
+
+    memory = Grid(["."])
+    memory.expand_for(Vec2(aoc.args.size-1, aoc.args.size-1), fill='.')
+
+    bytes_ = list(Vec2.from_str(line, split=',') for line in inputs)
+    num_bytes = min(len(bytes_), aoc.args.bytes)
+    for byte in bytes_[:num_bytes]:
+        memory[byte] = '#'
+
+    start = (0, 0)
+    end = (memory.width()-1, memory.height()-1)
+
+    neighbour_func = partial(neighbours, grid=memory)
+    came_from, _, _ = a_star(start, end, neighbours=neighbour_func)
+    path = reconstruct_path(came_from, start, end)
+
+    if aoc.args.verbose or aoc.args.progress:
+        overlays = [{pos: 'O' for pos in path},
+                    {start: 'S', end: 'E'},]
+        print(memory.render_with_overlays(overlays))
+    print(f"p1: {len(path)-1}")
+
+    for byte in bytes_[num_bytes:]:
+        memory[byte] = '#'
+        came_from, _, _ = a_star(start, end, neighbours=neighbour_func)
+        path = reconstruct_path(came_from, start, end)
+        if len(path) == 0:
+            print(f"p2: {byte[0]},{byte[1]}")
+            break
+
+
+if __name__ == "__main__":
+    main()

2024/18/script.py

@@ -3,10 +3,10 @@ My solutions to the yearly Advents of Code
 
 <!-- AOC TILES BEGIN -->
 <h1 align="center">
-  Advent of Code - 193/484 ⭐
+  Advent of Code - 195/486 ⭐
 </h1>
 <h1 align="center">
-  2024 - 32 ⭐ - Python
+  2024 - 34 ⭐ - Python
 </h1>
 <a href="2024/1/script.py">
   <img src=".aoc_tiles/tiles/2024/01.png" width="161px">
@@ -59,6 +59,9 @@ My solutions to the yearly Advents of Code
 <a href="2024/17/script.py">
   <img src=".aoc_tiles/tiles/2024/17.png" width="161px">
 </a>
+<a href="2024/18/script.py">
+  <img src=".aoc_tiles/tiles/2024/18.png" width="161px">
+</a>
 <h1 align="center">
   2023 - 47 ⭐ - Python
 </h1>