diff --git a/days/comp.py b/days/comp.py
index 509c5bc..36d174c 100644
--- a/days/comp.py
+++ b/days/comp.py
@@ -1,4 +1,4 @@
-from typing import List, Dict, Tuple, Iterator
+from typing import Dict, Tuple, Iterator, Iterable, Union
 
 
 class OpcodeComputer():
@@ -55,7 +55,7 @@ class OpcodeComputer():
             pass
         return (int(i[-2:]), a, b, c)
 
-    def process_op(self, inp: List[int] = [])\
+    def process_op(self, inp: Union[Iterator[int], Iterable[int]] = [])\
             -> Iterator[int]:
         """Run program code
 
@@ -75,6 +75,8 @@ class OpcodeComputer():
         pc: int = 0
         mem = self.memory
         cmd: int = mem[pc]
+        input: Iterator[int] = iter(inp)
+        popcount = 0
 
         while cmd != 99:
             cmd, a, b, c = self.parse_param(pc, mem, base)
@@ -85,7 +87,8 @@ class OpcodeComputer():
                 mem[c] = read(a) * read(b)
                 pc += 4
             elif cmd == 3:
-                mem[a] = int(inp.pop(0))
+                mem[a] = int(next(input))
+                popcount += 1
                 pc += 2
             elif cmd == 4:
                 yield read(a)