diff --git a/app.py b/app.py
index 9c0c34c..f54a6ed 100644
--- a/app.py
+++ b/app.py
@@ -98,7 +98,7 @@ class Reaction(db.Model):
 def choose_new_next(min_like_num=MIN_LIKE_NUM):
     for story in Story.query.filter_by(is_tree=False).all():
         last_paragraph_id = story.tail
-        next_one = Paragraph.query.filter_by(parent_id=last_paragraph_id, is_hidden=False)\
+        next_one = Paragraph.query.filter_by(story_id=story.id, parent_id=last_paragraph_id, is_hidden=False)\
                                   .order_by(Paragraph.like_num.desc()).first()
         if next_one and next_one.like_num >= min_like_num:
             story.text += next_one.text
@@ -106,7 +106,35 @@ def choose_new_next(min_like_num=MIN_LIKE_NUM):
             story.tail = next_one.id
             next_one.is_chosen = True
 
-        db.session.commit()
+    for story in Story.query.filter_by(is_tree=True).all():
+        _max = story.total_like_num
+        _tail = story.tail
+        _sum_dict = {}
+
+        def _get_like_sum(p):
+            if p.id in _sum_dict:
+                return _sum_dict[p.id]
+            s = p.like_num + (p.parent_id and _get_like_sum(Paragraph.query.get(p.parent_id)))
+            _sum_dict[p.id] = s
+            return s
+
+        for p in Paragraph.query.filter(Paragraph.like_num >= min_like_num)\
+                .filter_by(story_id=story.id, is_hidden=False).all():
+            if _get_like_sum(p) > _max:
+                _max = _get_like_sum(p)
+                _tail = p.id
+
+        p = Paragraph.query.get(_tail)
+        _text = p.text
+        while p.parent_id:
+            p = Paragraph.query.get(p.parent_id)
+            _text = p.text + _text
+
+        story.total_like_num = _max
+        story.tail = _tail
+        story.text = _text
+
+    db.session.commit()
 
 
 def sample_question(qs, n=3):