def test_simple_reroute_4():
"""
1
/ \
6---2
/ \ / \
5 - 4 - 3
"""
g = Graph()
edges = [(1, 2), (2, 3), (3, 4), (4, 5), (5, 6), (6, 1), (2, 6), (2, 4),
(6, 2)]
for s, e in edges:
g.add_edge(s, e, 1, bidirectional=True)
g.del_edge(4, 5)
loads = {1: [1, 2, 3, 4], 3: [3, 2, 1], 6: [6, 2]}
sequence = resolve(g, loads)
assert sequence == [{
1: (1, 2)
}, {
1: (2, 4)
}, {
3: (3, 2)
}, {
3: (2, 1)
}, {
6: (6, 2)
}]
g.del_edge(2, 4)
sequence = resolve(g, loads)
assert sequence == [{
1: (1, 2)
}, {
3: (3, 4)
}, {
1: (2, 3)
}, {
3: (4, 2)
}, {
3: (2, 1)
}, {
6: (6, 2)
}, {
1: (3, 4)
}]
def test_3_trains():
"""
Two trains (abc & d) are going east. One train is going west (efgh).
a-b-c--0-0-0--d--0--e-f-g-h
\---0---/ \-0-/
1-2-3--4-5-6--7--8---9-10-11-12
\---13--/ \-14-/
The solution is given by side stepping abc & d and letting efgh pass.
"""
g = Graph()
edges = [(3, 13), (13, 7), (7, 14), (14, 9)]
for a, b in zip(range(1, 12), range(2, 13)):
edges.append((a, b))
for s, e in edges:
g.add_edge(s, e, 1, bidirectional=True)
loads = {
'a': [1, 10],
'b': [2, 11],
'c': [3, 12],
'd': [8, 9], # east bound
'e': [9, 1],
'f': [10, 2],
'g': [11, 3],
'h': [12, 4] # west bound
}
sequence = resolve(g, loads)
assert sequence is not None
def test_clockwise_rotation():
""" A simple loop of 4 locations, where 3 loads need to move
clockwise. """
g = Graph()
edges = [
(1, 2),
(2, 3),
(3, 4),
(4, 1),
]
for s, e in edges:
g.add_edge(s, e, 1, bidirectional=True)
loads = {1: [1, 2], 2: [2, 3], 3: [3, 4]} # position 4 is empty.
sequence = resolve(g, loads)
assert sequence == [
{
3: (3, 4)
}, # first move.
{
2: (2, 3)
}, # second move.
{
1: (1, 2)
}
], sequence # last move.
def test_simple_reroute_3():
""" Loop with 6 nodes:
1 <--> 2 <--> 3 <--> 4 <-- 5 <--> 6 <--> (1)
"""
g = Graph()
edges = [(1, 2), (2, 3), (3, 4), (4, 5), (5, 6), (6, 1)]
for s, e in edges:
g.add_edge(s, e, 1, bidirectional=True)
g.del_edge(4, 5)
loads = {1: [1, 2, 3], 2: [3, 2, 1]}
sequence = resolve(g, loads)
assert sequence == [{
1: (1, 6)
}, {
2: (3, 2)
}, {
2: (2, 1)
}, {
1: (6, 5)
}, {
1: (5, 4)
}, {
1: (4, 3)
}], sequence
def test_5x5_graph():
g = graph5x5()
loads = {
'a': [6],
'b': [11, 1],
'c': [16, 2],
'd': [17, 4],
'e': [19, 5],
'f': [20, 3]
}
sequence = resolve(g, loads)
assert sequence == [{
'a': (6, 7)
}, {
'b': (11, 6)
}, {
'b': (6, 1)
}, {
'a': (7, 6)
}, {
'c': (16, 11)
}, {
'd': (17, 18)
}, {
'd': (18, 13)
}, {
'd': (13, 14)
}, {
'd': (14, 9)
}, {
'd': (9, 4)
}, {
'f': (20, 15)
}, {
'f': (15, 14)
}, {
'f': (14, 13)
}, {
'f': (13, 8)
}, {
'f': (8, 3)
}, {
'e': (19, 20)
}, {
'e': (20, 15)
}, {
'e': (15, 10)
}, {
'e': (10, 5)
}, {
'c': (11, 12)
}, {
'c': (12, 7)
}, {
'c': (7, 2)
}], sequence
def test_simple_reroute():
""" to loads on a collision path. """
g = Graph()
for s, e in [(1, 2), (2, 3)]:
g.add_edge(s, e, 1, bidirectional=True)
for s, e in [(1, 4), (4, 3)]:
g.add_edge(s, e, 1, bidirectional=False)
loads = {1: [1, 2, 3], 2: [3, 2, 1]}
sequence = resolve(g, loads)
assert sequence == [{1: (1, 4)}, {2: (3, 2)}, {2: (2, 1)}, {1: (4, 3)}]
def test_2_trains():
"""
two trains of loads are approaching each other.
train 123 going from 1 to 14
train 4567 going from 14 to 1.
At intersection 4 train 123 can be broken apart and
buffered, so that train 4567 can pass.
The reverse (buffering train 4567) is not possible.
"""
g = Graph()
edges = [
(1, 2),
(2, 3),
(3, 4),
(4, 5),
(4, 6),
(4, 7),
(4, 8),
(5, 9),
(6, 9),
(7, 9),
(8, 9),
(9, 10),
(10, 11),
(11, 12),
(12, 13),
(13, 14),
]
for s, e in edges:
g.add_edge(s, e, 1, bidirectional=True)
loads = {
41: [1, 2, 3, 4, 5, 9, 10, 11, 12],
42: [2, 3, 4, 5, 9, 10, 11, 12, 13],
43: [3, 4, 5, 9, 10, 11, 12, 13, 14],
44: [11, 10, 9, 5, 4, 3, 2, 1],
45: [12, 11, 10, 9, 5, 4, 3, 2],
46: [13, 12, 11, 10, 9, 5, 4, 3],
47: [14, 13, 12, 11, 10, 9, 5, 4],
}
sequence = resolve(g, loads)
assert sequence == [{
43: (3, 4)
}, {
43: (4, 6)
}, {
42: (2, 3)
}, {
42: (3, 4)
}, {
42: (4, 7)
}, {
41: (1, 2)
}, {
41: (2, 3)
}, {
41: (3, 4)
}, {
41: (4, 5)
}, {
44: (11, 10)
}, {
44: (10, 9)
}, {
44: (9, 8)
}, {
44: (8, 4)
}, {
44: (4, 3)
}, {
44: (3, 2)
}, {
44: (2, 1)
}, {
45: (12, 11)
}, {
45: (11, 10)
}, {
45: (10, 9)
}, {
45: (9, 8)
}, {
45: (8, 4)
}, {
45: (4, 3)
}, {
45: (3, 2)
}, {
46: (13, 12)
}, {
46: (12, 11)
}, {
46: (11, 10)
}, {
46: (10, 9)
}, {
46: (9, 8)
}, {
46: (8, 4)
}, {
46: (4, 3)
}, {
47: (14, 13)
}, {
47: (13, 12)
}, {
47: (12, 11)
}, {
47: (11, 10)
}, {
47: (10, 9)
}, {
47: (9, 8)
}, {
47: (8, 4)
}, {
43: (6, 9)
}, {
43: (9, 10)
}, {
43: (10, 11)
}, {
43: (11, 12)
}, {
43: (12, 13)
}, {
43: (13, 14)
}, {
42: (7, 9)
}, {
42: (9, 10)
}, {
42: (10, 11)
}, {
42: (11, 12)
}, {
42: (12, 13)
}, {
41: (5, 9)
}, {
41: (9, 10)
}, {
41: (10, 11)
}, {
41: (11, 12)
}], sequence