Question

我必须使用Adjacency List或Matrix创建图形，并包含添加Vertex和Edge的函数。然而，我在同一行中不断得到不同的错误。我在

中收到此错误

def getConnection(self):
    return self.Edge[()]

这就是我所得到的就是这样。我试过了

return self.Edge()

和

return self.Edge[]

但我发现其他类型的错误。我需要在这里更改什么？

#Graph for Reference and use in BFS and DFS
graph = {'0': ['2'],
         '1': ['3', '0'],
         '2': ['3', '4'],
         '3': ['2', '4', '5'],
         '4': ['5', '6'],
         '5': ['6', '7'],
         '6': ['7', '8'],
         '7': ['8', '9'],
         '8': ['9', '0'],
         '9': ['0', '5'] }

class Vertex:

    def __init__(self, Label, Edge):
        self.Label = 0
        self.Edge = []

    def AddNeighbour(self, neighbour, weight=0):
        self.Connection[neighbour] = weight

    def __str__(self):
        return str(self.Label) + ' connected to: ' + str([i.Label for i in self.Edge])

    def getConnection(self):
        return self.Edge[()]

    def getLabel(self):
        return self.Label

class Graph:
    def __init__(self):
        self.VertexList = {}
        self.NumVertices = 0

    def AddVertex(self, Label):
        self.NumVertices = self.NumVertices + 1
        NewVertex = Vertex(Label, None)
        self.VertexList[Label] = NewVertex
        return NewVertex

    def GetVertex(self,n):
        if n in self.VertexList:
            return self.VertexList[n]
        else:
            return None

    def __contains__(self,n):
        return n in self.VertexList

    def AddNeighbour(self, neighbour, weight=0):
        self.Connection[neighbour] = weight

    def AddEdge(self,f,t,cost=0):
        if f not in self.VertexList:
            NewVertex = self.AddVertex(f)
        if t not in self.VertexList:
            NewVertex = self.AddVertex(t)


    def GetVertices(self):
        return self.VertexList.Label()

    def __iter__(self):
        return iter(self.VertexList.values())

g = Graph()
for i in range(10):
    g.AddVertex(i)

g.VertexList

g.AddEdge(0,2,0)
g.AddEdge(0,3,0)
g.AddEdge(1,3,0)
g.AddEdge(1,0,0)
g.AddEdge(2,3,0)
g.AddEdge(2,4,0)
g.AddEdge(3,2,0)
g.AddEdge(3,4,0)
g.AddEdge(3,5,0)
g.AddEdge(4,5,0)
g.AddEdge(4,6,0)
g.AddEdge(5,6,0)
g.AddEdge(5,7,0)
g.AddEdge(6,7,0)
g.AddEdge(6,8,0)
g.AddEdge(7,8,0)
g.AddEdge(7,9,0)
g.AddEdge(8,9,0)
g.AddEdge(8,0,0)
g.AddEdge(9,0,0)
g.AddEdge(9,5,0)

for v in g:
    for w in v.getConnection():
        print("( %s , %s )" % (v.getLabel(), w.getLabel()))

Answer 1

由于您将Edge定义为列表，因此可以返回：

列表本身：return self.Edge
列表的副本：return self.Edge[:]
列表中的元素：return self.Edge[i]
列表的一部分：return self.Edge[i:j]

当然，在最后两种情况下，您必须分别定义和初始化i和j。如果不使用，它们将分别表示列表的开头和结尾（即self.Egde[:j]将返回到列表j的所有元素的列表。关于该主题可能有许多变化：最后一个元素，两个元素，......

类型错误：列表索引必须是整数，而不是元组

1 个答案: