【算法——Python实现】无权图（稠密图、稀疏图）及图的遍历

# _*_ encoding:utf-8 _*_
"""
图
"""

from random import randint
import time
import copy
import Queue


class DenseGraph(object):
    """稠密图 - 邻接矩阵"""
    def __init__(self, n, directed):
        self.n = n  # 图中的点数
        self.m = 0  # 图中的边数
        self.directed = directed  # bool值，表示是否为有向图
        self.g = [[False for _ in range(n)] for _ in range(n)]  # 矩阵初始化都为False的二维矩阵

    def V(self):
        # 返回图中点数
        return self.n

    def E(self):
        # 返回图中边数
        return self.m

    def addEdge(self, v, w):
        # v和w中增加一条边，v和w都是[0,n-1]区间
        if v >= 0 and v < n and w >= 0 and w < n:
            if self.hasEdge(v, w):
                return None
            self.g[v][w] = True
            if not self.directed:
                self.g[w][v] = True
            self.m += 1

    def hasEdge(self, v, w):
        # v和w之间是否有边，v和w都是[0,n-1]区间
        if v >= 0 and v < n and w >= 0 and w < n:
            return self.g[v][w]

    class adjIterator(object):
        """相邻节点迭代器"""
        def __init__(self, graph, v):
            self.G = graph  # 需要遍历的图
            self.v = v  # 遍历v节点相邻的边
            self.index = 0  # 遍历的索引

        def __iter__(self):
            return self

        def next(self):
            while self.index < self.G.V():