diff --git a/2019/day20.py b/2019/day20.py
index 4809728..7ff8515 100644
--- a/2019/day20.py
+++ b/2019/day20.py
@@ -4,11 +4,82 @@ from string import ascii_uppercase
 from grid import Grid
 
 
+EX1 = [
+    "         A           ",
+    "         A           ",
+    "  #######.#########  ",
+    "  #######.........#  ",
+    "  #######.#######.#  ",
+    "  #######.#######.#  ",
+    "  #######.#######.#  ",
+    "  #####  B    ###.#  ",
+    "BC...##  C    ###.#  ",
+    "  ##.##       ###.#  ",
+    "  ##...DE  F  ###.#  ",
+    "  #####    G  ###.#  ",
+    "  #########.#####.#  ",
+    "DE..#######...###.#  ",
+    "  #.#########.###.#  ",
+    "FG..#########.....#  ",
+    "  ###########.#####  ",
+    "             Z       ",
+    "             Z       ",
+]
+EX2 = [
+    "             Z L X W       C                 ",
+    "             Z P Q B       K                 ",
+    "  ###########.#.#.#.#######.###############  ",
+    "  #...#.......#.#.......#.#.......#.#.#...#  ",
+    "  ###.#.#.#.#.#.#.#.###.#.#.#######.#.#.###  ",
+    "  #.#...#.#.#...#.#.#...#...#...#.#.......#  ",
+    "  #.###.#######.###.###.#.###.###.#.#######  ",
+    "  #...#.......#.#...#...#.............#...#  ",
+    "  #.#########.#######.#.#######.#######.###  ",
+    "  #...#.#    F       R I       Z    #.#.#.#  ",
+    "  #.###.#    D       E C       H    #.#.#.#  ",
+    "  #.#...#                           #...#.#  ",
+    "  #.###.#                           #.###.#  ",
+    "  #.#....OA                       WB..#.#..ZH",
+    "  #.###.#                           #.#.#.#  ",
+    "CJ......#                           #.....#  ",
+    "  #######                           #######  ",
+    "  #.#....CK                         #......IC",
+    "  #.###.#                           #.###.#  ",
+    "  #.....#                           #...#.#  ",
+    "  ###.###                           #.#.#.#  ",
+    "XF....#.#                         RF..#.#.#  ",
+    "  #####.#                           #######  ",
+    "  #......CJ                       NM..#...#  ",
+    "  ###.#.#                           #.###.#  ",
+    "RE....#.#                           #......RF",
+    "  ###.###        X   X       L      #.#.#.#  ",
+    "  #.....#        F   Q       P      #.#.#.#  ",
+    "  ###.###########.###.#######.#########.###  ",
+    "  #.....#...#.....#.......#...#.....#.#...#  ",
+    "  #####.#.###.#######.#######.###.###.#.#.#  ",
+    "  #.......#.......#.#.#.#.#...#...#...#.#.#  ",
+    "  #####.###.#####.#.#.#.#.###.###.#.###.###  ",
+    "  #.......#.....#.#...#...............#...#  ",
+    "  #############.#.#.###.###################  ",
+    "               A O F   N                     ",
+    "               A A D   M   "                  ,
+]
+
+
 def main():
     with open("day20.txt") as input_file:
         lines = [l.rstrip() for l in input_file.readlines()]
-    maze = Maze(lines, value_factory=str)
+    lines = EX2
 
+    # Part 1
+    maze = Maze(lines)
+    maze.find_portals()
+    maze.dumb_print()
+    min_steps = maze.count_min_steps(maze.entry, maze.exit)
+    print("Min steps:", min_steps)
+
+    # Part 2
+    maze = Maze(lines, recurse=True)
     maze.find_portals()
     maze.dumb_print()
     min_steps = maze.count_min_steps(maze.entry, maze.exit)
@@ -23,14 +94,15 @@ class Maze(Grid):
     ENTRY_DG = "AA"
     EXIT_DG = "ZZ"
 
-    def __init__(self, lines, *args, **kwargs):
-        super().__init__(*args, **kwargs)
+    def __init__(self, lines, recurse=False):
+        super().__init__(value_factory=str, lines=lines)
         self.entry = None
         self.exit = None
         self.portals = {}
-        for y, line in enumerate(lines):
-            for x, value in enumerate(line):
-                self.setv(x, y, value)
+        self.recurse = recurse
+        self.portal_is_outer = {}
+        self.height = len(lines)
+        self.width = max(len(line) for line in lines)
 
     def find_portals(self):
         portals = defaultdict(list)
@@ -41,12 +113,14 @@ class Maze(Grid):
                     rrv = self.getv(x + 2, y)
                     portal_pos = (x + 2, y) if rrv == Maze.TILE_PATH else (x - 1, y)
                     portals[v + rv].append(portal_pos)
+                    self.portal_is_outer[portal_pos] = x == 0 or x == self.width - 2
                     continue
                 dv = self.getv(x, y + 1)
                 if dv and dv in ascii_uppercase:
                     ddv = self.getv(x, y + 2)
                     portal_pos = (x, y + 2) if ddv == Maze.TILE_PATH else (x, y - 1)
                     portals[v + dv].append(portal_pos)
+                    self.portal_is_outer[portal_pos] = y == 0 or y == self.height - 2
         for n, p in portals.items():
             if n == "AA":
                 self.entry = p[0]
@@ -60,49 +134,49 @@ class Maze(Grid):
         for y, row in self.g.items():
             for x, v in row.items():
                 if (x, y) in self.portals:
-                    v = "░"
+                    v = "o" if self.portal_is_outer[(x, y)] else "i"
                 if (x, y) in (self.entry, self.exit):
                     v = "▒"
                 print(v, end="")
             print()
 
     def bfs(self, start, end):
-        discovered = Grid(value_factory=bool)
-        discovered.setv(start[0], end[1], True)
+        discovered = defaultdict(lambda: Grid(value_factory=bool))
+        discovered[0].setv(start[0], end[1], True)
         parents = {}
-        q = [start]
+        q = [(start, 0)]
         while q:
-            pos = q.pop(0)
-            if pos == end:
+            pos, level = q.pop(0)
+            if pos == end and (not self.recurse or level == 0):
                 return parents
             nears = self.near_objects(pos)
+            is_portal = pos in self.portals
+            if is_portal:
+                nears[self.portals[pos]] = Maze.TILE_PATH
             for near_pos, near_tile in nears.items():
                 if near_tile != Maze.TILE_PATH:
                     continue
-                if discovered.getv(near_pos[0], near_pos[1]):
+                near_level = level
+                if self.recurse and is_portal and near_pos == self.portals[pos]:
+                    near_level += -1 if self.portal_is_outer[pos] else 1
+                if discovered[near_level].getv(near_pos[0], near_pos[1]):
                     continue
-                discovered.setv(near_pos[0], near_pos[1], True)
-                parents[near_pos] = pos
-                q.append(near_pos)
+                discovered[near_level].setv(near_pos[0], near_pos[1], True)
+                parents[(near_pos, near_level)] = (pos, level)
+                q.append((near_pos, near_level))
         return None
     
     def count_min_steps(self, start, end):
         parents = self.bfs(start, end)
         count = 0
-        pos = end
-        while pos != start:
-            pos = parents[pos]
+        pos = (end, 0)
+        while pos != (start, 0):
             count += 1
-            if pos in self.portals:  # One more step to traverse portal.
+            parent = parents[pos]
+            if pos[1] != parent[1]:
                 count += 1
+            pos = parent
         return count
-    
-    def near_objects(self, p):
-        nears = super().near_objects(p)
-        for near in list(nears):
-            if near in self.portals:
-                nears[self.portals[near]] = Maze.TILE_PATH
-        return nears
 
 
 if __name__ == "__main__":