from collections import deque
class TreeNode(object):
def __init__(self, x):
self.val = x
self.left = None
self.right = None
class Tree(object):
def __init__(self):
self.root = None
def construct_tree(self, values=None):
if not values:
return None
self.root = TreeNode(values[0])
queue = deque([self.root])
leng = len(values)
nums = 1
while nums < leng:
node = queue.popleft()
if node:
node.left = TreeNode(values[nums]) if values[nums] else None
queue.append(node.left)
if nums + 1 < leng:
node.right = TreeNode(values[nums + 1]) if values[nums + 1] else None
queue.append(node.right)
nums += 1
nums += 1
def bfs(self):
ret = []
queue = deque([self.root])
while queue:
node = queue.popleft()
if node:
ret.append(node.val)
queue.append(node.left)
queue.append(node.right)
return ret
def bfs(tree):
if not tree:
return None
stack = [tree]
ret = []
while stack:
node = stack.pop(0)
ret.append(node.val)
if node.left:
stack.append(node.left)
if node.right:
stack.append(node.right)
return ret
if __name__ == '__main__':
t = Tree()
t.construct_tree([1, 2, 6, 4, 3, 7, 5])
print t.bfs()
print bfs(t.root)
