"""
# @Time  : 2020/11/8
# @Author : Jimou Chen
"""


# 廣搜
def bfs(graph, start):
  queue = [start] # 先把起點入隊列
  visited = set() # 訪問國的點加入
  visited.add(start)

  while len(queue):
    vertex = queue.pop(0)
    # 找到隊列首元素的連接點
    for v in graph[vertex]:
      if v not in visited:
        queue.append(v)
        visited.add(v)
    # 打印彈出隊列的該頭元素
    print(vertex, end=' ')


if __name__ == '__main__':
  graph = {
    'A': ['B', 'D', 'I'],
    'B': ['A', 'F'],
    'C': ['D', 'E', 'I'],
    'D': ['A', 'C', 'F'],
    'E': ['C', 'H'],
    'F': ['B', 'H'],
    'G': ['C', 'H'],
    'H': ['E', 'F', 'G'],
    'I': ['A', 'C']
  }

  bfs(graph, 'A')

"""
# @Time  : 2020/11/8
# @Author : Jimou Chen
"""


# 深搜
def dfs(graph, start):
  stack = [start]
  visited = set()
  visited.add(start)

  while len(stack):
    vertex = stack.pop() # 找到棧頂元素
    for v in graph[vertex]:
      if v not in visited:
        stack.append(v)
        visited.add(v)

    print(vertex, end=' ')


if __name__ == '__main__':
  graph = {
    'A': ['B', 'D', 'I'],
    'B': ['A', 'F'],
    'C': ['D', 'E', 'I'],
    'D': ['A', 'C', 'F'],
    'E': ['C', 'H'],
    'F': ['B', 'H'],
    'G': ['C', 'H'],
    'H': ['E', 'F', 'G'],
    'I': ['A', 'C']
  }

  dfs(graph, 'E')