cleanup

y2020/p20.py

@@ -4,13 +4,13 @@ import collections
 import itertools
 import sys
 import math
+from functools import reduce
 
 import toolkit
 
 
 def apply(cell):
-    key, *fns = cell
-    string = tiles[key]
+    string, *fns = cell
     for fn in fns:
         if fn is not None:
             string = fn(string)
@@ -28,8 +28,8 @@ def render(grid):
     return '\n'.join(
         '\n'.join(''.join([n[1:-1]
             for n in ln])
-        for ln in zip(*[apply(cell).splitlines()[1:-1] for cell in row]))
-        for row in grid
+        for ln in zip(*[apply(grid[y, x]).splitlines()[1:-1] for x in range(size)]))
+        for y in range(size)
     )
 
 
@@ -53,6 +53,29 @@ def rot90(n):
     return inner
 
 
+def noop(string):
+    return string
+
+
+def variants(string):
+    alts = [noop, flipH], [noop, flipV], [noop, rot90(1), rot90(2), rot90(3)]
+    for ops in itertools.product(*alts):
+        yield reduce(lambda s, f: f(s), ops, string), ops
+
+
+def search_in(source, target):
+    source_lns = source.splitlines()
+    target_lns = target.splitlines()
+    h, w = len(target_lns), len(target_lns[0])
+    out = []
+    for y in range(len(source_lns)):
+        for x in range(len(source_lns[0])):
+            window = '\n'.join(ln[x:x + w] for ln in source_lns[y:y + h])
+            if re.fullmatch(target, window):
+                out.append((x, y))
+    return out
+
+
 text = sys.stdin.read().strip()
 tiles = {}
 borders = {}
@@ -61,18 +84,16 @@ for line in text.split('\n\n'):
     tid = int(title.split()[1])
     tiles[tid] = content
     borders[tid] = get_borders(content)
-
-
-size = int(len(borders) ** 0.5)
-
+size = int(len(tiles) ** 0.5)
 
 adj = collections.defaultdict(set)
 for (aid, A), (bid, B) in itertools.combinations(borders.items(), 2):
     if set(A) & set(B):
         adj[aid].add(bid)
         adj[bid].add(aid)
-
 corn = [v for v, ks in adj.items() if len(ks) == 2]
+print(math.prod(corn))
+
 
 gids = [[None for _ in range(size)] for _ in range(size)]
 
@@ -90,43 +111,33 @@ for y in range(2, size):
         gids[y][x], = adj[gids[y][x - 1]] & adj[gids[y - 1][x]] - {gids[y - 1][x - 1]}
 
 
-grid = [[(gids[y][x],) for x in range(size)] for y in range(size)]
-grid[0][0] += (flipV,)
-
 options = list(itertools.product([None, flipH], [None, flipV], [None] + [rot90(n) for n in range(3)]))
 
+grid = {(y, x): (tiles[gids[y][x]],) for x in range(size) for y in range(size)}
+grid[0, 0] = (flipV(grid[0, 0][0]),)
+
+
 for x in range(1, size):
-    goal = [ln[-1] for ln in apply(grid[0][x - 1]).splitlines()]
+    goal = [ln[-1] for ln in apply(grid[0, x - 1]).splitlines()]
     for chain in options:
-        if goal == [ln[0] for ln in apply(grid[0][x] + chain).splitlines()]:
-            grid[0][x] += chain
+        if goal == [ln[0] for ln in apply(grid[0, x] + chain).splitlines()]:
+            grid[0, x] += chain
             break
 
 for y in range(1, size):
     for x in range(size):
-        goal = apply(grid[y - 1][x]).splitlines()[-1]
+        goal = apply(grid[y - 1, x]).splitlines()[-1]
         for chain in options:
-            if goal == apply(grid[y][x] + chain).splitlines()[0]:
-                grid[y][x] += chain
+            if goal == apply(grid[y, x] + chain).splitlines()[0]:
+                grid[y, x] += chain
                 break
 
 
-monster = '''                  #
-#    ##    ##    ###
- #  #  #  #  #  #   '''
-kuk, W, H = toolkit.read_image(monster)
-goal = re.compile(toolkit.render(kuk).replace('\n', '').replace(' ', '.'))
-
-cnt = 0
-for chain in options:
-    grody = apply2(render(grid), chain)
-    grok = [list(line) for line in grody.splitlines()]
-    for y in range(len(grok) - H):
-        for x in range(len(grok[0]) - W):
-            sample = ''.join(''.join(grok[y + dy][x + dx] for dx in range(W)) for dy in range(H))
-            cnt += bool(goal.fullmatch(sample))
-    if cnt:
-        break
-
-print(grody)
-print(grody.count('#') - cnt * monster.count('#'))
+monster = '''
+..................#.
+#....##....##....###
+.#..#..#..#..#..#...
+'''[1:-1]
+src = render(grid)
+found = max([search_in(pic, monster) for pic, _ in variants(src)], key=len)
+print(src.count('#') - len(found) * monster.count('#'))