diff --git a/src/tools/aoc.py b/src/tools/aoc.py
index ad46931..daf71d8 100644
--- a/src/tools/aoc.py
+++ b/src/tools/aoc.py
@@ -32,6 +32,7 @@ class AOCDay:
         self._current_test_file = None
         self._current_test_solution = None
         self.DP = {}
+        self.SEEN = set()
         self.__main_progress_bar_id = None
         self.__main_progress_bar_pos = 0
         self.progress_bars = {}
@@ -68,12 +69,14 @@ class AOCDay:
 
             if not measure_runtime or case_count < len(self.inputs[part]) - 1:
                 self.DP = {}
+                self.seen_reset()
                 answer = self._call_part_func(self.part_func[part])
             else:
                 stopwatch = StopWatch(auto_start=False)
                 self.__main_progress_bar_pos = 1
                 for _ in tqdm(range(timeit_number), desc=f"Part {part+1}", leave=False):
                     self.DP = {}
+                    self.seen_reset()
                     stopwatch.start()
                     answer = self._call_part_func(self.part_func[part])
                     stopwatch.stop()
@@ -284,6 +287,16 @@ class AOCDay:
         pbar = self.progress_bars[bar_id]
         pbar.update(add)
 
+    def seen_reset(self):
+        self.SEEN = set()
+
+    def seen(self, value: Any, auto_add: bool = True) -> bool:
+        if value in self.SEEN:
+            return True
+        if auto_add:
+            self.SEEN.add(value)
+        return False
+
 
 def print_solution(
     day: int,