Day 10 (reduced memory usage)

day10/part2.py

@@ -1,16 +1,7 @@
-import numpy as np
-
 lines = sorted(int(x.strip()) for x in open("input.txt"))
 
-lines.append(lines[-1]+3)
-lines.insert(0, 0)
-lines = np.array(lines)
-
-diff = lines[1:] - lines[:-1]
-
 one_count = 0
 possibilities = 1
-
 one_cache = [1]
 
 
@@ -22,12 +13,16 @@ def count_one_possibilities(one_cnt: int):
 
 # only 3 and 1 differences are available
 # 3 has to be taken / calculate possibilities for 1 hops
-for num in diff:
-    if num == 1:
+prev = 0
+for line in lines:
+    diff = line-prev
+    prev = line
+    if diff == 1:
         one_count += 1
-    elif num == 3:
+    elif diff == 3:
         possibilities *= count_one_possibilities(one_count)
         one_count = 0
+possibilities *= count_one_possibilities(one_count)
 
 print(possibilities)  # 64793042714624
 print(one_cache)  # {0: 1, 1: 1, 2: 2, 3: 4, 4: 7}