graph.py
#!/usr/bin/python
class Edge(object):
def __init__(self, start, end, weight):
self.startNodeId = start
self.endNodeId = end
self.weight = weight
class Node(object):
def __init__(self, nodeId, edgeList):
self.nodeId = nodeId
self.edgeList = edgeList
class Path(object):
def __init__(self, curNodeId):
self.visited = False
self.weight = 8888
self.curNodeId = curNodeId
self.routeList = []
class Graph(object):
def __init__(self, nodeList):
self.nodeList = nodeList
self.pathDic = {}
def initPaths(self, originNodeId):
self.pathDic = {}
originNode = None
for node in self.nodeList:
if node.nodeId == originNodeId:
originNode = node
self.pathDic[node.nodeId] = Path(node.nodeId)
if originNode is None:
print "originNode is none"
return
else:
for edge in originNode.edgeList:
path = self.pathDic[edge.endNodeId]
if path is None:
print "path is None"
return
else:
path.weight = edge.weight
path.routeList.append(originNodeId)
path = self.pathDic[originNodeId]
path.weight = 0
path.visit = True
path.routeList.append(originNodeId)
def getMinPath(self, originNodeId):
destNode = None
weight = 8888
for node in self.nodeList:
path = self.pathDic[node.nodeId]
if path.visited == False and path.weight < weight:
weight = path.weight
destNode = node
return destNode
def dijkstra(self, originNodeId, destNodeId):
self.initPaths(originNodeId)
curNode = self.getMinPath(originNodeId)
while curNode is not None:
curPath = self.pathDic[curNode.nodeId]
curPath.visited = True
for edge in curNode.edgeList:
minPath = self.pathDic[edge.endNodeId]
if minPath.weight > (curPath.weight + edge.weight):
minPath.weight = curPath.weight + edge.weight
minPath.routeList = curPath.routeList + [curNode.nodeId]
curNode = self.getMinPath(originNodeId)
route = self.pathDic[destNodeId].routeList
if route == []:
return route
else:
return route + [destNodeId]
test.py
#!/usr/bin/python
#coding:utf-8
from dijkstra import Edge as Edge
from dijkstra import Node as Node
from dijkstra import Graph as Graph
edge11 = Edge("A", "B", 10)
edge12 = Edge("A", "C", 20)
edge13 = Edge("A", "E", 30)
edge21 = Edge("B", "C", 5)
edge22 = Edge("B", "E", 10)
edge31 = Edge("C", "D", 30)
edge51 = Edge("E", "D", 10)
node1 = Node("A", [edge11, edge12, edge13])
node2 = Node("B", [edge21, edge22])
node3 = Node("C", [edge31])
node4 = Node("D", [])
node5 = Node("E", [edge51])
graph = Graph([node1, node2, node3, node4, node5])
startNodeId = raw_input("请输入起点: ")
endNodeId = raw_input("请输入终点: ")
print "最短路径:", graph.dijkstra(startNodeId, endNodeId), "\n"
