diff --git a/day10/part2.py b/day10/part2.py
index dd71695..ed990b2 100644
--- a/day10/part2.py
+++ b/day10/part2.py
@@ -11,15 +11,12 @@ diff = lines[1:] - lines[:-1]
 one_count = 0
 possibilities = 1
 
-one_cache = {}
+one_cache = [1]
 
 
 def count_one_possibilities(one_cnt: int):
-    if one_cnt not in one_cache:
-        if one_cnt <= 1:
-            one_cache[one_cnt] = 1
-        else:
-            one_cache[one_cnt] = sum(count_one_possibilities(less) for less in range(max(0, one_cnt - 3), one_cnt))
+    for idx in range(len(one_cache), one_cnt+1):
+        one_cache.append(sum(one_cache[-3:]))
     return one_cache[one_cnt]