diff --git a/day1/part1.py b/day1/part1.py
index 840128e..f9e30f2 100644
--- a/day1/part1.py
+++ b/day1/part1.py
@@ -1,10 +1,14 @@
 from common import parse, split_and_sort
 
 
+def solve(l1: list[int], l2: list[int]) -> int:
+    assert len(l1) == len(l2)
+    return sum(map(lambda i: abs(l1[i] - l2[i]), range(len(l1))))
+
+
 def main() -> None:
     l1, l2 = split_and_sort(parse("input"))
-    assert len(l1) == len(l2)
-    print(sum(map(lambda i: abs(l1[i] - l2[i]), range(len(l1)))))
+    print(solve(l1, l2))
 
 
 if __name__ == "__main__":
diff --git a/day1/part2.py b/day1/part2.py
index 9b5b741..de490b9 100644
--- a/day1/part2.py
+++ b/day1/part2.py
@@ -1,9 +1,13 @@
 from common import parse, split
 
 
+def solve(l1: list[int], l2: list[int]) -> int:
+    return sum(map(lambda x: x * len(list(filter(lambda y: y == x, l2))), l1))
+
+
 def main():
     l1, l2 = split(parse("input"))
-    print(sum(map(lambda x: x * len(list(filter(lambda y: y == x, l2))), l1)))
+    print(solve(l1, l2))
 
 
 if __name__ == "__main__":