diff --git a/generate_rules.py b/generate_rules.py
index f203e45..929deca 100644
--- a/generate_rules.py
+++ b/generate_rules.py
@@ -18,7 +18,7 @@ class WorkGroup:
         self.track = track if track is not None else 'none'  # haben alle aks einen track?
         self.projector = 'true' if projector else 'false'
         self.reso = 'true' if reso else 'false'
-        self.length = floor(length / SLOT_LEN) + 1
+        self.length = floor((length-1) / SLOT_LEN) + 1
         if self.length > 2:
             print(f"Warning, length of workgroup {id} greater than 2.")
             self.length = 2
@@ -53,13 +53,17 @@ class WorkGroup:
 
 
 class Room:
-    def __init__(self, id, n_places, projector):  # TODO internet, whiteboard & co.
+    def __init__(self, id, n_places, projector, is_pool):  # TODO internet, whiteboard & co.
         self.id = id  # must be int
         self.n_places = n_places
         self.projector = 'true' if projector else 'false'
+        self.is_pool = is_pool
 
     def __str__(self):
-        return f'room({self.id}, {self.n_places}, {self.projector}).'
+        pool_rule = ''
+        if self.is_pool:
+            pool_rule = f'\npool({self.id}).'
+        return f'room({self.id}, {self.n_places}, {self.projector}).{pool_rule}'
 
 
 class Timeslot:
@@ -110,7 +114,7 @@ def parse_rooms(data):
     rooms = []
     id_to_room = {}
     for i, room in enumerate(data['rooms']):
-        rooms.append(Room(room['id'], room['places'], room['projector']))  # TODO internet, whiteboard & co.
+        rooms.append(Room(room['id'], room['places'], room['projector'], room['pool']))  # TODO internet, whiteboard & co.
         id_to_room[room['id']] = i
     return rooms, id_to_room
 
@@ -145,10 +149,13 @@ LENGTH = { schedule(AK,TIMESLOT,ROOM): timeslot(TIMESLOT,_,_,_,_), room(ROOM,_,_
 schedule(AK,TIMESLOT2,ROOM) :- ak(AK,_,_,_,_,2), schedule(AK,TIMESLOT1,ROOM), timeslot(TIMESLOT1,ORDER1,_,_,DAY), timeslot(TIMESLOT2,ORDER2,_,_,DAY), timeslot(TIMESLOT3,ORDER3,_,_,_), ORDER2 != ORDER1+1, ORDER1 = ORDER3+1, not schedule(AK,TIMESLOT3,ROOM) .
 
 """
-
+lengths = defaultdict(int)
 for workgroup in workgroups:
+    lengths[workgroup.length] += 1
     rules += str(workgroup) + '\n'
 
+print(lengths, lengths[1] + lengths[2]*2)
+
 for room in rooms:
     rules += str(room) + '\n'
 
@@ -209,7 +216,10 @@ for workgroup in workgroups:
                 f':- schedule({workgroup.id}, TIMESLOT, _), timeslot(TIMESLOT, ORDER, _, _, _), ORDER >= {first_timeslot}, ORDER <= {last_timeslot}.')
             rules += f':- schedule({workgroup.id}, TIMESLOT, _), timeslot(TIMESLOT, ORDER, _, _, _), ORDER >= {first_timeslot}, ORDER <= {last_timeslot}.\n'
 
-rules += "#show schedule/3."
+rules += "pool_schedule(ROOM) :- schedule(_,_,ROOM), pool(ROOM).\n"\
+        "poolpen(T) :- T = {pool_schedule(_)}.\n"\
+        "#minimize { T : poolpen(T) }.\n" \
+         "#show schedule/3."
 
 #######################
 #  GENERATE SCHEDULE  #
@@ -220,7 +230,7 @@ output_file_name = "generated_rules.pl"
 open(output_file_name, 'w').write(rules)
 
 # create subprocess definition
-process = ['clingo', output_file_name]
+process = ['clingo', output_file_name, '--outf=2']
 
 # run subprocess, not sure, if busy-waiting..
 completed_process = subprocess.run(process, universal_newlines=True, stdout=subprocess.PIPE, stderr=subprocess.DEVNULL)
@@ -237,16 +247,12 @@ else:
     print('SATISFIABLE, outputting schedule...')
     import re
 
-    try:
-        match = re.match('(.|\n)*Answer: (.+)\n(.*)\nSATISFIABLE', output)
-        schedules_string = match.group(3)
-    except Exception as e:
-        print(e)
-        print(output)
+    output = json.loads(output)
+
     schedules = []
     workgroup_to_schedule = defaultdict(list)
-    for i, schedule in enumerate(schedules_string.split('schedule')[1:]):
-        match = re.match('\((.+),"(.+)#(.+)#.+",(.+)\)', schedule)
+    for i, schedule in enumerate(output['Call'][0]['Witnesses'][-1]['Value']):
+        match = re.match('schedule\((.+),"(.+)#(.+)#.+",(.+)\)', schedule)
         try:
             workgroup_id = id_to_workgroup[int(match.group(1))]
             room_id = id_to_room[int(match.group(4))]
diff --git a/temp b/temp
new file mode 100644
index 0000000..e69de29