Python实现数据结构 图
邻接矩阵
class Vertex:
def __init__(self, node):
self.id = node
# Mark all nodes unvisited
self.visited = False def addNeighbor(self, neighbor, G):
G.addEdge(self.id, neighbor) def getConnections(self, G):
return G.adjMatrix[self.id] def getVertexID(self):
return self.id def setVertexID(self, id):
self.id = id def setVisited(self):
self.visited = True def __str__(self):
return str(self.id) class Graph:
def __init__(self, numVertices=10, directed=False):
self.adjMatrix = [[None] * numVertices for _ in range(numVertices)]
self.numVertices = numVertices
self.vertices = []
self.directed = directed
for i in range(0, numVertices):
newVertex = Vertex(i)
self.vertices.append(newVertex) def addVertex(self, vtx, id): #增加点,这个function没有扩展功能
if 0 <= vtx < self.numVertices:
self.vertices[vtx].setVertexID(id) def getVertex(self, n):
for vertxin in range(0, self.numVertices):
if n == self.vertices[vertxin].getVertexID():
return vertxin
return None def addEdge(self, frm, to, cost=0): #返回全部连线/航线
#print("from",frm, self.getVertex(frm))
#print("to",to, self.getVertex(to))
if self.getVertex(frm) is not None and self.getVertex(to) is not None:
self.adjMatrix[self.getVertex(frm)][self.getVertex(to)] = cost
if not self.directed:
# For directed graph do not add this
self.adjMatrix[self.getVertex(to)][self.getVertex(frm)] = cost def getVertices(self):
vertices = []
for vertxin in range(0, self.numVertices):
vertices.append(self.vertices[vertxin].getVertexID())
return vertices def printMatrix(self):
for u in range(0, self.numVertices):
row = []
for v in range(0, self.numVertices):
row.append(str(self.adjMatrix[u][v]) if self.adjMatrix[u][v] is not None else '/')
print(row) def getEdges(self):
edges = []
for v in range(0, self.numVertices):
for u in range(0, self.numVertices):
if self.adjMatrix[u][v] is not None:
vid = self.vertices[v].getVertexID()
wid = self.vertices[u].getVertexID()
edges.append((vid, wid, self.adjMatrix[u][v]))
return edges def getNeighbors(self, n):
neighbors = []
for vertxin in range(0, self.numVertices):
if n == self.vertices[vertxin].getVertexID():
for neighbor in range(0, self.numVertices):
if (self.adjMatrix[vertxin][neighbor] is not None):
neighbors.append(self.vertices[neighbor].getVertexID())
return neighbors def isConnected(self, u, v):
uidx = self.getVertex(u)
vidx = self.getVertex(v)
return self.adjMatrix[uidx][vidx] is not None def get2Hops(self, u): #转一次机可以到达哪里
neighbors = self.getNeighbors(u)
print(neighbors)
hopset = set()
for v in neighbors:
hops = self.getNeighbors(v)
hopset |= set(hops)
return list(hopset)
邻接表
import sys
class Vertex:
def __init__(self, node):
self.id = node
self.adjacent = {}
#为所有节点设置距离无穷大
self.distance = sys.maxsize
# 标记未访问的所有节点
self.visited = False
# Predecessor
self.previous = None def addNeighbor(self, neighbor, weight=0):
self.adjacent[neighbor] = weight # returns a list
def getConnections(self): # neighbor keys
return self.adjacent.keys() def getVertexID(self):
return self.id def getWeight(self, neighbor):
return self.adjacent[neighbor] def setDistance(self, dist):
self.distance = dist def getDistance(self):
return self.distance def setPrevious(self, prev):
self.previous = prev def setVisited(self):
self.visited = True def __str__(self):
return str(self.id) + ' adjacent: ' + str([x.id for x in self.adjacent]) def __lt__(self, other):
return self.distance < other.distance and self.id < other.id class Graph:
def __init__(self, directed=False):
# key is string, vertex id
# value is Vertex
self.vertDictionary = {}
self.numVertices = 0
self.directed = directed def __iter__(self):
return iter(self.vertDictionary.values()) def isDirected(self):
return self.directed def vectexCount(self):
return self.numVertices def addVertex(self, node):
self.numVertices = self.numVertices + 1
newVertex = Vertex(node)
self.vertDictionary[node] = newVertex
return newVertex def getVertex(self, n):
if n in self.vertDictionary:
return self.vertDictionary[n]
else:
return None def addEdge(self, frm, to, cost=0):
if frm not in self.vertDictionary:
self.addVertex(frm)
if to not in self.vertDictionary:
self.addVertex(to) self.vertDictionary[frm].addNeighbor(self.vertDictionary[to], cost)
if not self.directed:
# For directed graph do not add this
self.vertDictionary[to].addNeighbor(self.vertDictionary[frm], cost) def getVertices(self):
return self.vertDictionary.keys() def setPrevious(self, current):
self.previous = current def getPrevious(self, current):
return self.previous def getEdges(self):
edges = []
for key, currentVert in self.vertDictionary.items():
for nbr in currentVert.getConnections():
currentVertID = currentVert.getVertexID()
nbrID = nbr.getVertexID()
edges.append((currentVertID, nbrID, currentVert.getWeight(nbr))) # tuple
return edges def getNeighbors(self, v):
vertex = self.vertDictionary[v]
return vertex.getConnections()
引入的这两段代码的原文链接:
https://www.cnblogs.com/kumata/p/9246502.html
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