Day 12 part 2

12/12.py

@@ -61,7 +61,7 @@ all_path = []
 explore_tree('start', visited_nodes, all_path, 0)
 
 print()
-print(f'listing all paths')
+print('listing all paths')
 for p in all_path:
     print(p)
 

12/12_2.py

@@ -0,0 +1,93 @@
+#!/usr/bin/env python
+# 2021 - Advent Of Code - 11
+
+GRID_SIZE = 10
+
+
+def parse_file(file):
+    with open(file) as f:
+        return [x.strip() for x in f.readlines()]
+
+
+def special_cave(point, twice_cave):
+    if point == twice_cave[0] and twice_cave[1] > 0:
+        print(f'Using special cave: {twice_cave}')
+        return True
+    return False
+
+
+def valid_destination(point, visited, twice_cave):
+    if point.isupper():
+        return True
+    if point not in visited:
+        return True
+    if point == twice_cave and visited.count(point) < 2:
+        print(f'Using special cave: {twice_cave}')
+        return True
+    return False
+
+
+def explore_tree(current_node, visited, paths_list, twice_cave, gen):
+    possible_path = [c for c in connections if current_node in c.split('-')]
+    print(f'\n{gen} current_node: {current_node}\t possible path: {possible_path}')
+    print(f'{gen} visited: {visited}')
+
+    for path in possible_path:
+        print(f'{gen} exploring {path}')
+        new_visited = list(visited)
+        # check end
+        if 'end' in path:
+            visited.append('end')
+            paths_list.add(tuple(visited))
+            print(f'{gen} keeping path: {visited}')
+            continue
+
+        nodes = path.split('-')
+        if nodes[0] == current_node:
+            if valid_destination(nodes[1], visited, twice_cave):
+                print(f'{gen} destination: {nodes[1]}')
+                new_visited.append(nodes[1])
+                explore_tree(nodes[1], list(new_visited), paths_list, twice_cave, gen+1)
+            else:
+                print(f'{gen} removing dest: {nodes[1]}')
+        else:
+            if valid_destination(nodes[0], visited, twice_cave):
+                print(f'{gen} destination: {nodes[0]}')
+                new_visited.append(nodes[0])
+                explore_tree(nodes[0], list(new_visited), paths_list, twice_cave, gen+1)
+            else:
+                print(f'{gen} removing dest: {nodes[0]}')
+
+
+# connections = parse_file('input_example3.txt')
+connections = parse_file('input.txt')
+print(f'connections: {connections}')
+
+points = set()
+for conn in connections:
+    p = conn.split('-')
+    points.add(p[0])
+    points.add(p[1])
+
+print(f'unique points: {points}')
+print()
+
+starting_positions = [c for c in connections if 'start' in c]
+ending_positions = [c for c in connections if 'end' in c]
+
+small_caves = [c for c in points if c != 'start' and c != 'end' and c.islower()]
+print(f'small caves: {small_caves}')
+
+visited_nodes = ['start']
+all_path = set()
+for cave in small_caves:
+    explore_tree('start', visited_nodes, all_path, cave, 0)
+
+explore_tree('start', visited_nodes, all_path, 'b', 0)
+
+print()
+print('listing all paths')
+for p in all_path:
+    print(p)
+
+print(f'{len(all_path)} paths')