1 files changed, 28 insertions, 0 deletions
diff --git a/day10/day10.py b/day10/day10.py
new file mode 100644
index 0000000..041c758
--- /dev/null
+++ b/day10/day10.py
@@ -0,0 +1,28 @@
+"""Day 10."""
+from collections import Counter
+from itertools import combinations
+from functools import lru_cache
+
+with open("input") as f:
+    orig_nums = sorted([int(x) for x in f.read().rstrip().split("\n")])
+
+rated_for = orig_nums[-1] + 3
+nums = [0] + orig_nums + [rated_for]
+diffs = [j - i for i, j in list(zip(nums[:-1], nums[1:]))]
+counter = Counter(diffs)
+
+# Part 1
+print(counter[1] * counter[3])
+
+@lru_cache(None)
+def arrangements(jolts, prev) -> int:
+    first, rest = jolts[0], jolts[1:]
+    if first - prev > 3:
+        return 0
+    elif not rest:
+        return 1
+    else:
+        return (arrangements(rest, first) + # Use first
+                arrangements(rest, prev))   # Skip first
+
+print(arrangements(tuple(orig_nums), 0))