diff --git a/task_3.py b/task_3.py
index 0e97389..c0309f3 100644
--- a/task_3.py
+++ b/task_3.py
@@ -92,10 +92,38 @@ def find_intersection(interval_A, interval_B) -> list:
     return [interval_begin, interval_end]
 
 
+def enlarge_elapsed_intervals(intervals):
+    # ключ - начало, значние - конец. Если по ключу "начало" уже есть
+    # значение, то сохраняем max(существующее, новое)
+    beginnings = {interval[0]: interval[1] for interval in intervals}
+    endings = {interval[1]: interval[0] for interval in intervals}
+
+    for interval in intervals:
+        begin = interval[0]
+        end = interval[1]
+
+        beginnings[begin] = max(beginnings[begin], end)
+        endings[end] = min(endings[end], begin)
+
+    print(f"{beginnings=}")
+    print(f"{endings=}")
+    beginnings_list = list(beginnings.values())
+    endings_lsit = list(endings.values())
+    test = [
+        [endings_lsit[i], beginnings_list[i]] for i in range(len(beginnings_list) - 1)
+    ]
+    return test
+
+
 def appearance(intervals):
     lesson = intervals["lesson"]
     pupil = intervals["pupil"]
     tutor = intervals["tutor"]
+    pupil2 = [pupil[i : i + 2] for i in range(0, len(pupil), 2)]
+    # print(f"{pupil2=}")
+    # pupil2 = enlarge_elapsed_intervals(pupil2)
+
+    enlarge_elapsed_intervals(test)
 
     # получаем все интервалы студента на уроке
     pupil_on_lesson = [