"""

Definition for a Directed graph node

class DirectedGraphNode:

def __init__(self, x):

self.label = x

self.neighbors = []

"""

class Solution:

"""

@param: graph: A list of Directed graph node

@return: Any topological order for the given graph.

"""

def topSort(self, graph):

ans = []

if not graph:

return ans

indegs = {}

for node in graph:

if node not in indegs:

indegs[node] = 0

for _node in node.neighbors:

if _node not in indegs:

indegs[_node] = 0

indegs[_node] += 1

queue = [node for node, indeg in indegs.items() if indeg == 0]

for node in queue:

ans.append(node)

for _node in node.neighbors:

indegs[_node] -= 1

if indegs[_node] == 0:

queue.append(_node)

return ans