关于Python 中出现的TypeError: missing 1 required positional argument

问题描述

开始学习python正在看数据结构 关于图的部分 这个是在实现一个图的深度优先遍历 和 广度优先遍历，但是在最后，也就是g.add_nodes([i+1 for i in range(10)])会显示TypeError: add_nodes() missing 1 required positional argument: ’nodelist’ 就完全不知道该怎么去解决，有没有大神可以指点一下。

这个是我的程序

class Graph(object):

def __init__(self, *args, **kwargs): self.node_neighbors = {} self.visited = {}def add_nodes(self,nodelist): for node in nodelist:self.add_node(node)def add_node(self,node): if node not in self.add_nodes():self.node_neighbors[node] = []def add_edge(self,edge): u, v = edge if(v not in self.node_neighbors[u]) and (u not in self.node_neighbors[v]):self.node_neighbors[u].append(u)if(u!=v): self.node_neighbors[v].append(u)def nodes(self): return self.node_neighbors.keys()def depth_first_search(self, root=None): order = [] def dfs(node):self.visited[node] = Trueorder.append(node)for n in self.node_neighbors[node]: if not n in self.visited:dfs(n) if root:dfs(root) for node in self.nodes():if not node in self.visited: dfs(node) print(order) return orderdef breadtg_frist_search(self, root = None): queue = [] order = [] def bfs():while len(queue) > 0: node = queue.pop() self.visited[node] = True for n in self.node_neighbors[node]:if (not n in self.visited) and (not n in queue): queue.append(n) order.append(n) if root:queue.append(root)order.append(root)bfs() for node in self.nodes():if not node in self.visited: queue.append(node) order.append(node) bfs() print(order) return order

if name == ’__main__’:

g = Graph()

g.add_nodes([i+1 for i in range(10)])g.add_edge((1, 2))g.add_edge((1, 3))g.add_edge((2, 4))g.add_edge((2, 5))g.add_edge((4, 8))g.add_edge((5, 8))g.add_edge((5, 9))g.add_edge((3, 6))g.add_edge((3, 7))g.add_edge((7, 10))g.add_edge((9, 10))print(’nodes:’ + g.nodes())order = g.breadtg_frist_search(1)order = g.depth_first_search(1)

问题解答

def add_node(self,node): if node not in self.add_nodes():self.node_neighbors[node] = []

if node not in self.add_nodes():中的add_nodes()需要参数,具体要什么看你自己了.