Python/graphs/g_topological_sort.py

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# Author: Phyllipe Bezerra (https://github.com/pmba)
clothes = {
0: "underwear",
1: "pants",
2: "belt",
3: "suit",
4: "shoe",
5: "socks",
6: "shirt",
7: "tie",
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8: "watch",
}
graph = [[1, 4], [2, 4], [3], [], [], [4], [2, 7], [3], []]
visited = [0 for x in range(len(graph))]
stack = []
def print_stack(stack, clothes):
order = 1
while stack:
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current_clothing = stack.pop()
print(order, clothes[current_clothing])
order += 1
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def depth_first_search(u, visited, graph):
visited[u] = 1
for v in graph[u]:
if not visited[v]:
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depth_first_search(v, visited, graph)
stack.append(u)
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def topological_sort(graph, visited):
for v in range(len(graph)):
if not visited[v]:
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depth_first_search(v, visited, graph)
if __name__ == "__main__":
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topological_sort(graph, visited)
print(stack)
print_stack(stack, clothes)