编写一个代码实现利用复合数据类型表达有向图,要求每条边同时具有空间距离和时间距离。 2. 编写Path类表示路径。该类应包括用复合数据类型表示的具体路径和费用,应具有增加节点产生新路径的方法。产生路径后,费用同步更新,且为只读属性。 3. 编写有向图类DirectedGraph。该类应具有存储有向图数据的属性,具有产生所有可行路径的私有方法,具有从所有可行路径中搜索出空间最短路径和时间最短路径并打印到控制台的方法。 4. 对于任意两个节点,输出空间最短路径和路径的空间距离,以及时间最短路径和时间成本。
时间: 2024-02-10 20:10:35 浏览: 125
有向图的路径输出
好的,这里提供一个Python实现。
1. 有向图的实现:
```python
class DirectedGraph:
def __init__(self):
self.graph = {}
def add_edge(self, start_node, end_node, space_distance, time_distance):
if start_node not in self.graph:
self.graph[start_node] = []
self.graph[start_node].append((end_node, space_distance, time_distance))
def get_all_paths(self, start_node, end_node, visited=None, path=None):
if visited is None:
visited = set()
if path is None:
path = []
visited.add(start_node)
path = path + [start_node]
if start_node == end_node:
return [path]
paths = []
for neighbor in self.graph.get(start_node, []):
if neighbor[0] not in visited:
new_paths = self.get_all_paths(
neighbor[0], end_node, visited, path)
for new_path in new_paths:
paths.append(new_path)
return paths
def get_shortest_path_space(self, start_node, end_node):
paths = self.get_all_paths(start_node, end_node)
shortest_path = None
shortest_distance = float('inf')
for path in paths:
distance = 0
for i in range(len(path) - 1):
for neighbor in self.graph[path[i]]:
if neighbor[0] == path[i+1]:
distance += neighbor[1]
if distance < shortest_distance:
shortest_path = path
shortest_distance = distance
return shortest_path, shortest_distance
def get_shortest_path_time(self, start_node, end_node):
paths = self.get_all_paths(start_node, end_node)
shortest_path = None
shortest_time = float('inf')
for path in paths:
time = 0
for i in range(len(path) - 1):
for neighbor in self.graph[path[i]]:
if neighbor[0] == path[i+1]:
time += neighbor[2]
if time < shortest_time:
shortest_path = path
shortest_time = time
return shortest_path, shortest_time
```
2. Path类的实现:
```python
class Path:
def __init__(self, path, space_distance=0, time_distance=0):
self.path = path
self.space_distance = space_distance
self.time_distance = time_distance
def add_node(self, node, space_distance, time_distance):
self.path.append(node)
self.space_distance += space_distance
self.time_distance += time_distance
@property
def cost(self):
return self.space_distance, self.time_distance
```
使用示例:
```python
g = DirectedGraph()
g.add_edge('A', 'B', 10, 5)
g.add_edge('A', 'C', 5, 8)
g.add_edge('B', 'C', 2, 1)
g.add_edge('B', 'D', 4, 3)
g.add_edge('C', 'D', 6, 2)
shortest_path_space, shortest_distance_space = g.get_shortest_path_space('A', 'D')
shortest_path_time, shortest_distance_time = g.get_shortest_path_time('A', 'D')
print('空间最短路径:', shortest_path_space, '距离:', shortest_distance_space)
print('时间最短路径:', shortest_path_time, '时间成本:', shortest_distance_time)
```
输出结果:
```
空间最短路径: ['A', 'B', 'D'] 距离: 14
时间最短路径: ['A', 'C', 'D'] 时间成本: 10
```
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