/
networkx_flow.py
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/
networkx_flow.py
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import click
import time
import networkx as nx
from networkx.algorithms.flow import edmonds_karp
from networkx.drawing.nx_pydot import write_dot
def parse_dicaps_graph(input_file):
with open(input_file, 'r') as f:
f.readline()
source = int(f.readline().split()[1])
sink = int(f.readline().split()[1])
G = nx.DiGraph()
for line in f.readlines():
_, u, v, c = line.split()
u = int(u)
v = int(v)
G.add_edge(u, v, capacity=int(c))
return G, source, sink
@click.command()
@click.option('--ek', is_flag=True)
@click.option('--draw', is_flag=True)
@click.argument('input_file')
def cli(ek, draw, input_file):
g, source, sink = parse_dicaps_graph(input_file)
if draw:
write_dot(g, 'graph.dot')
return
if ek:
print('Using Edmonds Karp')
flow_func = edmonds_karp
else:
print('Using Preflow Push')
flow_func = None
t0 = time.time()
flow = nx.maximum_flow_value(g, source, sink, flow_func=flow_func)
t1 = time.time()
print("Max Flow Solution: {0}".format(flow))
print("Runtime: {0}s".format(t1 - t0))
if __name__ == '__main__':
cli()