Create bfs_dfs.py

Author: Owen-CH-Leung

reinforcement_learning/bfs_dfs.py

@@ -0,0 +1,37 @@
+import networkx as nx
+
+def breadth_first_search(graph, start):
+    visited = []
+    queue = [start]
+    while queue:        
+        node = queue.pop(0)
+        if node not in visited:
+            visited.append(node)
+            neighbors = graph.neighbors(node)           
+            for n in neighbors:
+                queue.append(n)
+    return visited
+
+def depth_first_search(graph, node, path=[]):
+    path += [node]
+    for n in graph.neighbors(node):
+        if n not in path:
+            path = depth_first_search(graph, n, path)
+    return path
+
+if __name__ == '__main__':
+    graph_dict = {'A':['B', 'C', 'D'],
+             'B':['E'],
+             'C':['F'],
+             'D':['G', 'H'],
+             'E':[],
+             'F':['I', 'J'],
+             'G':[],
+             'H':[],
+             'I':[],
+             'J':[]
+            } 
+    G = nx.DiGraph(graph_dict)
+    nx.draw(G, with_labels=True)
+    print(breadth_first_search(G, 'A'))
+    print(depth_first_search(G, 'A'))