def dijkstra(aGraph, start):
pq = PriorityQueue()
start.setDistance(0)
pq.buildHeap([(v.getDistance(), v) for v in aGraph])
while not pq.isEmpty():
currentVert = pq.delMin()
for nextVert in currentVert.getConnections():
newDist = currentVert.getDistance() \
+ currentVert.getWeight(nextVert)
if newDist < nextVert.getDistance():
nextVert.setDistance(newDist)
nextVert.setPred(currentVert)
pq.decreaseKey(nextVert, newDist)
def prim(G, start):
pq = PriorityQueue()
for v in G:
v.setDistance(sys.maxsize)
v.setPred(None)
start.setDistance(0)
pq.buildHeap([(v.getDistance(), v) for v in G])
while not pq.isEmpty():
currentVert = pq.delMin()
for nextVert in currentVert.getConnections():
newCost = currentVert.getWeight(nextVert)
if nextVert in pq and newCost < nextVert.getDistance():
nextVert.setPred(currentVert)
nextVert.setDistance(newCost)
pq.decreaseKey(nextVert, newCost)
def dijkstra(graph,start): pq = PriorityQueue() for v in G: v.setDistance(sys.maxsize) v.setPred(None) start.setDistance(0) pq.buildHeap([(v.getDistance(),v) for v in graph]) while not pq.isEmpty(): currentVert = pq.delMin() for nextVert in currentVert.getConnections(): newDist = currentVert.getWeight(nextVert) + currentVert.getDistance() if newDist < nextVert.getDistance(): nextVert.setDistance(newDist) nextVert.setPred(currentVert) pq.decreaseKey(nextVert,newDist)
def prim(G,start): pq = PriorityQueue() #initialize values for v in G: v.setDistance(sys.maxsize) v.setPred(None) start.setDistance(0) pq.buildHeap([(v.getDistance(),v) for v in G]) while not pq.isEmpty(): currentVert = pq.delMin() for nextVert in currentVert.getConnections(): newCost = currentVert.getWeight(nextVert) + currentVert.getDistance() if nextVert in pq and newCost < nextVert.getDistance(): nextVert.setPred(currentVert) nextVert.setDistance(newCost) pq.decreaseKey(nextVert,newCost)
