diff --git a/day-10/day-10.py b/day-10/day-10.py
index 2328279..5eb6b59 100644
--- a/day-10/day-10.py
+++ b/day-10/day-10.py
@@ -27,19 +27,18 @@ def part_1(input):
 
 def part_2(input):
     result = 0
-    lines = input.copy()
     scores = []
-    for line in input:
+    for line in input.copy():
         seen = []
         for c in line.rstrip():
             if c in o_chars:
                 seen.append(c)
             elif o_chars.index(seen[-1]) != c_chars.index(c):
-                lines.remove(line)
+                input.remove(line)
                 break
             else:
                 del seen[-1]
-    for line in lines:
+    for line in input:
         seen = []
         for c in line.rstrip():
             if c in o_chars: