Solve 2024 day 8

2024/d7.py

@@ -1,23 +1,10 @@
 from lib import get_data
-from lib import Grid2D
 from lib import ints
-from collections import defaultdict
-
-data = """ 190: 10 19
-3267: 81 40 27
-83: 17 5
-156: 15 6
-7290: 6 8 6 15
-161011: 16 10 13
-192: 17 8 14
-21037: 9 7 18 13
-292: 11 6 16 20
-"""
 
 data = get_data(__file__)
 
 
-def comp(acc, rest, part_2=False):
+def combs(acc, rest, part_2=False):
     if rest == []:
         return acc
 
@@ -27,16 +14,16 @@ def comp(acc, rest, part_2=False):
         nacc.append(a * rest[0])
         if part_2:
             nacc.append(int(str(a) + str(rest[0])))
-    return comp(nacc, rest[1:], part_2)
+    return combs(nacc, rest[1:], part_2)
 
 
 t1, t2 = 0, 0
 for line in data.splitlines():
     xs = ints(line)
     expected = xs[0]
-    if xs[0] in comp([xs[1]], xs[2:]):
+    if xs[0] in combs([xs[1]], xs[2:]):
         t1 += xs[0]
-    if xs[0] in comp([xs[1]], xs[2:], True):
+    if xs[0] in combs([xs[1]], xs[2:], True):
         t2 += xs[0]
 
 print(t1)

2024/d8.py

@@ -0,0 +1,34 @@
+from lib import get_data
+from lib import Grid2D
+from itertools import combinations
+from collections import defaultdict
+
+data = get_data(__file__)
+g = Grid2D(data)
+
+d = defaultdict(list)
+
+for row in range(g.n_rows):
+    for col in range(g.n_cols):
+        p = (row, col)
+        if g[p] != ".":
+            d[g[p]].append((row, col))
+
+aa = set()
+bb = set()
+for coords in d.values():
+    for c, d in combinations(coords, 2):
+        bb.add(c)
+        bb.add(d)
+        for a, b in [(c, d), (d, c)]:
+            d = b[0] - a[0], b[1] - a[1]
+            a = b[0] + d[0], b[1] + d[1]
+            if g.contains(a):
+                aa.add(a)
+            a = b[0] + d[0], b[1] + d[1]
+            while g.contains(a):
+                bb.add(a)
+                a = a[0] + d[0], a[1] + d[1]
+
+print(len(aa))
+print(len(bb))

README.md

@@ -298,4 +298,5 @@ and focus. Of course, learning more algorithms and techniques helps.
 - Day 5: `00:07:07   679      0   00:23:02  1998      0`
 - Day 6: `00:09:43  1082      0   00:16:29   464      0`
 - Day 7: `00:12:29  2058      0   00:13:08  1170      0`
-- Day 8:
+- Day 8: `00:15:59  1742      0   00:26:56  2190      0`
+