Use defaultdict

1 files changed, 3 insertions, 3 deletions

diff --git a/2025/07/b.py b/2025/07/b.py
index 4457654..0a8672e 100644
--- a/2025/07/b.py
+++ b/2025/07/b.py
@@ -1,15 +1,15 @@
 import fileinput
+from collections import defaultdict
 
 with fileinput.input() as lines:
         rows = [line[:-1] for line in lines]
 
 pos = {rows[0].find('S'): 1}
 for row in rows[1:]:
-        newpos = {}
+        newpos = defaultdict(int)
         for p, w in pos.items():
                 for pp in [p-1,p+1] if row[p] == '^' else [p]:
-                        t = newpos.get(pp, 0)
-                        newpos[pp] = t + w
+                        newpos[pp] += w
         pos = dict(newpos)
 
 print(sum(pos.values()))