diff --git a/days/comp.py b/days/comp.py
index a3f171e..5f6a507 100644
--- a/days/comp.py
+++ b/days/comp.py
@@ -14,6 +14,10 @@ class OpcodeComputer():
         https://adventofcode.com/2019/day/5
 
     """
+    memory = []
+
+    def __init__(self, mem: List[int]) -> None:
+        self.memory = mem
 
     def parse_param(self, pc: int, mem: List[int]) \
             -> Tuple[int, int, int, int]:
@@ -38,7 +42,7 @@ class OpcodeComputer():
             pass
         return (int(i[-2:]), a, b, c)
 
-    def process_op(self, mem: List[int]) -> int:
+    def process_op(self) -> int:
         """Run program code
 
         Args:
@@ -48,7 +52,9 @@ class OpcodeComputer():
             int: Content in memory at position 0
         """
         pc: int = 0
+        mem = list(self.memory)
         cmd: int = mem[pc]
+
         while cmd != 99:
             cmd, a, b, c = self.parse_param(pc, mem)
             if cmd == 1:
diff --git a/days/day2.py b/days/day2.py
index ccb5e51..7280505 100644
--- a/days/day2.py
+++ b/days/day2.py
@@ -12,7 +12,7 @@ class Day2(unittest.TestCase):
             code: List[int] = [int(k) for k in fp.readline().split(',')]
         code[1] = 12
         code[2] = 2
-        self.assertEqual(OpcodeComputer().process_op(code), 5098658)
+        self.assertEqual(OpcodeComputer(code).process_op(), 5098658)
 
     def test_day2b(self):
         with open(self.inputfile) as fp:
@@ -24,7 +24,7 @@ class Day2(unittest.TestCase):
             code[1] = a
             code[2] = b
 
-            result = OpcodeComputer().process_op(code)
+            result = OpcodeComputer(code).process_op()
             if result == 19690720:
                 break
         self.assertEqual(100 * a + b, 5064)
diff --git a/days/day5.py b/days/day5.py
index abb3272..37fcfc0 100644
--- a/days/day5.py
+++ b/days/day5.py
@@ -12,21 +12,21 @@ class Day5(unittest.TestCase):
     def test_day5a(self):
         output_val = []
 
-        sut = comp.OpcodeComputer()
+        sut = comp.OpcodeComputer(self.get_code())
         # replace input() and print() to simulate user behavior
         comp.input = lambda: 1
         comp.print = lambda s: output_val.append(s)
 
-        sut.process_op(self.get_code())
+        sut.process_op()
         self.assertEqual(int(output_val[-1]), 8332629)
 
     def test_day5b(self):
         output_val = []
 
-        sut = comp.OpcodeComputer()
+        sut = comp.OpcodeComputer(self.get_code())
         # replace input() and print() to simulate user behavior
         comp.input = lambda: 5
         comp.print = lambda s: output_val.append(s)
 
-        sut.process_op(self.get_code())
+        sut.process_op()
         self.assertEqual(int(output_val[-1]), 8805067)