# dictionary_adjacency_list.py

# dictionary_adjacency_list.py

graph = {
  '7' : ['19','21', '14'],
  '19': ['1', '12', '31'],
  '21': [],
  '14': ['23', '6'],
  '1' : [],
  '12': [],
  '31': [],
  '23': [],
  '6' : []
}

visited = [] # List of visited nodes of graph.
def dfs(visited, graph, node):

    for neighbor in graph[node]:
        dfs(visited, graph, neighbor)
    print(node)

print("Following is the Depth-First Search")
dfs(visited, graph, '7')
print("visited=",visited)