使用类在python中创建图形数据结构

时间:2018-09-22 02:36:40

标签: python python-3.x data-structures graph-algorithm

我正在尝试创建某种类型的类,该类的通用性足以用于树和图。

class Node:
    def __init__(self, value, children=[]):
        self.value = value
        self.children = children

    def add_child(self, child):
        self.children.append(child)

    def add_children(self, list_of_children):
        for child in list_of_children:
            self.add_child(child)

def letterGraph():
    a = Node('A')
    b = Node('B')
    c = Node('C')
    d = Node('D')
    c = Node('C')
    e = Node('E')
    f = Node('F')
    g = Node('G')

    a.add_children([b, c])
    b.add_children([a, d, e])
    c.add_children([a, d])
    d.add_children([b, c, e, g, f])
    e.add_children([b, d, g])
    f.add_children([d, g])
    g.add_children([e, d, f])

    return a

它似乎可以与树配合使用,但是对于图而言,当它向当前节点添加一个子节点时,也会将该同一个子节点添加到当前节点的子节点中。

  

示例:

     

current_node:一个

     

a.add_children([b,c])

     

current_node.children:[b,c]

     

b.children:[b,c]`

2 个答案:

答案 0 :(得分:1)

我个人根本不会在构造函数中调用此函数。您没有使用它,为什么要在那儿使用它?

在测试时使用__repr__使其更具可读性也很有帮助。

class Node:
    def __init__(self, value):    # Take children out of constructor
        self.value = value
        self.children = []     # Initialise children in the function

    def add_child(self, child):
        self.children.append(child)

    def add_children(self, list_of_children):
        for child in list_of_children:
            self.add_child(child)

    def __repr__(self): 
        return self.value    # I am not a machine 

def letterGraph():
    a = Node('A')
    b = Node('B')
    c = Node('C')
    d = Node('D')
    c = Node('C')
    e = Node('E')
    f = Node('F')
    g = Node('G')

    a.add_children([b, c])
    b.add_children([a, d, e])
    c.add_children([a, d])
    d.add_children([b, c, e, g, f])
    e.add_children([b, d, g])
    f.add_children([d, g])
    g.add_children([e, d, f])

    print(a.children)
    print(b.children)


letterGraph()

答案 1 :(得分:0)

这就是我在@amadan的帮助下解决的方法

infinity = float('inf')

class Node:
    def __init__(self, value, children = None, depth=None):
        self.value = value
        self.children = children
        self.depth = depth

    def add_child(self, child, depth= None):
        if self.children is None:
            self.children = [child]
            self.depth = depth
        else:
            self.children.append(child)

    def add_child_by_value(self, value):
        self.children.add_child(Node(value))

    def add_children(self, list_of_children):
        for child in list_of_children:
            self.add_child(child)

    def is_leaf(self):
        return self.children is None