Add day11, 2025

Author: snhansen

2025/day11/solution.py

@@ -0,0 +1,26 @@
+import networkx as nx
+from functools import cache
+
+with open("input") as f:
+    inp = f.read().strip().split("\n")
+
+g = nx.DiGraph()
+for line in inp:
+    in_, outs = line.split(": ")
+    for out in outs.split():
+        g.add_edge(in_, out)
+
+# Part 1
+print(len(list(nx.all_simple_paths(g, "you", "out"))))
+
+# Part 2
+@cache
+def no_paths(fr, to, fft = False, dac = False):
+    fft = fft or (fr == "fft")
+    dac = dac or (fr == "dac")
+    if fr == to:
+        return 1 if fft and dac else 0
+    return sum(no_paths(neighbor, to, fft, dac) for neighbor in g.neighbors(fr))
+
+
+print(no_paths("svr", "out"))