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graph.py
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1110 lines (1005 loc) · 31.2 KB
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import math as _math
from copy import deepcopy as _deepcopy
import numpy as _np
COLOR_WHITE = 0
COLOR_GRAY = 1
COLOR_BLACK = 2
DIRECTION_NONE = ' '
DIRECTION_TO = '→'
DIRECTION_FROM = '←'
DIRECTION_BOTH = '←→'
class Vertex:
'''
图的顶点
'''
def __init__(self, key = None):
'''
图的顶点
Args
===
`key` : 顶点关键字
'''
self.key = key
self.color = COLOR_WHITE
self.d = _math.inf
self.pi = None
self.f = _math.inf
self.weightkey = 0
self.isvisit = False
def resetpara(self):
'''
复位所有属性
'''
self.color = COLOR_WHITE
self.d = _math.inf
self.pi = None
self.f = _math.inf
def __hash__(self):
code = self.color.__hash__()
code = code * 37 + self.key.__hash__()
code = code * 37 + self.pi.__hash__()
code = code * 37 + self.d.__hash__()
code = code * 37 + self.f.__hash__()
return code
def __str__(self):
return '[key:{} color:{} d:{} f:{} pi:{}]'.format(self.key, \
self.color, self.d, self.f, self.pi)
def __lt__(self, other):
if type(other) is Vertex:
return self.weightkey < other.weightkey
else:
return self.weightkey < other
def __gt__(self, other):
if type(other) is Vertex:
return self.weightkey > other.weightkey
else:
return self.weightkey > other
def __le__(self, other):
if type(other) is Vertex:
return self.weightkey <= other.weightkey
else:
return self.weightkey <= other
def __ge__(self, other):
if type(other) is Vertex:
return self.weightkey >= other.weightkey
else:
return self.weightkey >= other
def __eq__(self, other):
if type(other) is Vertex:
return self.weightkey == other.weightkey
else:
return self.weightkey == other
def __ne__(self, other):
if type(other) is Vertex:
return self.weightkey != other.weightkey
else:
return self.weightkey != other
class Edge:
'''
图的边,包含两个顶点
'''
def __init__(self, vertex1 : Vertex = None, \
vertex2 : Vertex = None, \
weight = 1, \
dir = DIRECTION_NONE,
):
'''
图的边,包含两个顶点
Args
===
`vertex1` : 边的一个顶点
`vertex2` : 边的另一个顶点
`dir` : 边的方向
DIRECTION_NONE : 没有方向
DIRECTION_TO : `vertex1` → `vertex2`
DIRECTION_FROM : `vertex1` ← `vertex2`
DIRECTION_BOTH : `vertex1` ←→ `vertex2`
'''
self.dir = dir
self.vertex1 = vertex1
self.vertex2 = vertex2
self.weight = weight
def __str__(self):
return str((self.vertex1.key, self.vertex2.key, self.dir, self.weight))
def __hash__(self):
code = self.dir.__hash__()
code = code * 37 + self.vertex1.__hash__()
code = code * 37 + self.vertex2.__hash__()
code = code * 37 + self.weight.__hash__()
return code
def __lt__(self, other):
if type(other) is Graph:
return self.weight < other.weight
else:
return self.weight < other
def __gt__(self, other):
if type(other) is Graph:
return self.weight > other.weight
else:
return self.weight > other
def __le__(self, other):
if type(other) is Graph:
return self.weight <= other.weight
else:
return self.weight <= other
def __ge__(self, other):
if type(other) is Graph:
return self.weight >= other.weight
else:
return self.weight >= other
def __eq__(self, other):
if type(other) is Graph:
return self.weight == other.weight
else:
return self.weight == other
def __ne__(self, other):
if type(other) is Graph:
return self.weight != other.weight
else:
return self.weight != other
class Graph:
'''
图`G=(V,E)`
'''
def __init__(self, vertexs : list = [], edges : list = []):
'''
图`G=(V,E)`
Args
===
`vertexs` : 图的顶点
`edges` : 图的边
'''
self.veterxs = vertexs
self.edges = edges
def clear(self):
'''
清除所有顶点和边
'''
self.veterxs = []
self.edges = []
def hasdirection(self):
'''
图`g`是否是有向图
'''
dir = False
for i in range(len(self.edges)):
dir = dir or self.edges[i].dir != DIRECTION_NONE
return dir
def veterxs_atkey(self, key):
'''
从顶点序列`vertexs`中返回键值为`key`的顶点
Args
===
`key` Vertex | int
'''
if type(key) is Vertex:
return key
for i in range(len(self.veterxs)):
if type(self.veterxs[i]) is not Vertex:
self.veterxs[i] = Vertex(self.veterxs[i])
if self.veterxs[i].key == key:
return self.veterxs[i]
def getvertexadj(self, v : Vertex):
'''
获取图中顶点`v`的邻接顶点序列
'''
v = self.veterxs_atkey(v)
adj = self.getadj_from_matrix()
if v is None:
return None
uindex = 0
for i in range(len(self.veterxs)):
if self.veterxs[i].key == v.key:
uindex = i
break
return adj[uindex]
def getedge(self, v1 : Vertex, v2 : Vertex):
'''
根据两个顶点获取边,若两个点不相邻,返回None
'''
if type(v1) is not Vertex:
v1 = self.veterxs_atkey(v1)
if type(v2) is not Vertex:
v2 = self.veterxs_atkey(v2)
for edge in self.edges:
if edge.vertex1.key == v1.key and edge.vertex2.key == v2.key:
return edge
elif edge.vertex2.key == v1.key and edge.vertex1.key == v2.key:
return edge
return None
def printadj(self):
'''
打印邻接表
'''
for v in self.veterxs:
v = self.veterxs_atkey(v)
for edge in self.edges:
if type(edge) is Edge:
pass
elif len(edge) == 2:
u, v = edge
edge = Edge(Vertex(u), Vertex(v))
else:
u, v, dir = edge
edge = Edge(Vertex(u), Vertex(v),dir=dir)
for v in self.veterxs:
list = self.getvertexadj(v)
print(v.key, end='→')
for e in list:
if type(e) is Vertex:
print(e.key, end=' ')
else:
print(e, end=' ')
print('')
def reset_vertex_para(self):
'''
复位所有顶点的参数
'''
for i in range(len(self.veterxs)):
self.veterxs[i].resetpara()
def addvertex(self, v):
'''
向图中添加结点`v`
Args
===
`v` : Vertex | List<Vertex> | List<string>
'''
if type(v) is list:
for node in v:
if type(node) is not Vertex:
key = node
node = Vertex(key)
self.veterxs.append(node)
return
if type(v) is not Vertex:
key = v
v = Vertex(key)
self.veterxs.append(v)
def addedgewithweight(self, v1, v2, weight, dir = DIRECTION_NONE):
'''
向图中添加边`edge`
Args
===
`v1` : 边的一个顶点
`v2` : 边的另一个顶点
`weight` : 边的权重
`dir` : 边的方向
DIRECTION_NONE : 没有方向
DIRECTION_TO : `vertex1` → `vertex2`
DIRECTION_FROM : `vertex1` ← `vertex2`
DIRECTION_BOTH : `vertex1` ←→ `vertex2`
'''
egde = Edge(Vertex(v1), Vertex(v2), weight, dir)
self.edges.append(egde)
def addedge(self, v1, v2, dir = DIRECTION_NONE):
'''
向图中添加边`edge`
Args
===
`v1` : 边的一个顶点
`v2` : 边的另一个顶点
`dir` : 边的方向
DIRECTION_NONE : 没有方向
DIRECTION_TO : `vertex1` → `vertex2`
DIRECTION_FROM : `vertex1` ← `vertex2`
DIRECTION_BOTH : `vertex1` ←→ `vertex2`
'''
egde = Edge(Vertex(v1), Vertex(v2), 1, dir)
self.edges.append(egde)
def getvertexfromedge(self, edge : Edge):
'''
获取边的两个顶点的引用
Args
===
`edge` : 边
Return
===
(u, v) :
'''
n = len(self.veterxs)
if type(edge) is Edge:
u, v, dir = edge.vertex1, edge.vertex2, edge.dir
for k in range(n):
if self.veterxs[k].key == u.key:
uindex = k
if self.veterxs[k].key == v.key:
vindex = k
return (self.veterxs[uindex], self.veterxs[vindex])
elif len(edge) == 2:
u, v = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
else:
u, v, dir = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
return (u, v)
def getadj_from_matrix(self):
'''
从邻接矩阵获得邻接列表
'''
matrix = self.matrix
n = self.vertex_num
adj = []
for i in range(n):
sub = []
for j in range(n):
if matrix[i][j] == 1:
sub.append(self.veterxs[j])
adj.append(sub)
return adj
@property
def adj(self):
'''
获取邻接表
'''
adj = []
n = len(self.veterxs)
if n == 0:
return []
for i in range(n):
sub = []
for edge in self.edges:
dir = ' '
if type(edge) is Edge:
u, v, dir = edge.vertex1, edge.vertex2, edge.dir
for k in range(n):
if self.veterxs[k].key == u.key:
uindex = k
if self.veterxs[k].key == v.key:
vindex = k
elif len(edge) == 2:
u, v = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
else:
u, v, dir = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
if dir == DIRECTION_TO and uindex == i:
val = self.veterxs[vindex]
for i in range(len(sub)):
if sub[i].key == val.key:
continue
sub.append(val)
elif dir == DIRECTION_FROM and vindex == i:
val = self.veterxs[uindex]
for i in range(len(sub)):
if sub[i].key == val.key:
continue
sub.append(val)
elif dir == DIRECTION_NONE and uindex == i:
val = self.veterxs[vindex]
for i in range(len(sub)):
if sub[i].key == val.key:
continue
sub.append(val)
elif dir == DIRECTION_NONE and vindex == i:
val = self.veterxs[uindex]
for i in range(len(sub)):
if sub[i].key == val.key:
continue
sub.append(val)
adj.append(sub)
return adj
@property
def matrix(self):
'''
获取邻接矩阵,并且其是一个对称矩阵
'''
n = len(self.veterxs)
if n == 0:
return []
mat = _np.zeros((n, n))
for edge in self.edges:
dir = ' '
if type(edge) is Edge:
u, v, dir = edge.vertex1, edge.vertex2, edge.dir
for k in range(n):
if self.veterxs[k].key == u.key:
uindex = k
if self.veterxs[k].key == v.key:
vindex = k
elif len(edge) == 2:
u, v = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
else:
u, v, dir = edge
uindex = self.veterxs.index(u)
vindex = self.veterxs.index(v)
if dir == DIRECTION_TO:
mat[uindex, vindex] = 1
elif dir == DIRECTION_FROM:
mat[vindex, uindex] = 1
else:
mat[uindex, vindex] = 1
mat[vindex, uindex] = 1
return mat
def gettranspose(self):
'''
获取图`g`的转置
'''
g_rev = _deepcopy(self)
for i in range(len(g_rev.edges)):
lastdir = g_rev.edges[i].dir
g_rev.edges[i].dir = self.__get_rev_dir(lastdir)
return g_rev
def __get_rev_dir(self, dir):
if dir == DIRECTION_FROM:
dir = DIRECTION_TO
elif dir == DIRECTION_TO:
dir = DIRECTION_FROM
else:
dir = DIRECTION_NONE
return dir
def buildrevedges(self):
'''
构造反向的有向图边
'''
newedges = []
n = len(self.edges)
for i in range(n):
edge = self.edges[i]
if type(edge) is Edge:
v1, v2, dir = edge.vertex1, edge.vertex2, edge.dir
else:
v1, v2, dir = edge
edge_rev = v2, v1, self.__get_rev_dir(dir)
newedges.append(edge_rev)
return newedges
def __buildBMatrix(self, B, v, i, j, v1, v2, dir):
if v1 != v and v2 != v:
B[i][j] = 0
elif v1 == v and dir == DIRECTION_TO:
B[i][j] = -1
elif v2 == v and dir == DIRECTION_FROM:
B[i][j] = -1
elif v1 == v and dir == DIRECTION_FROM:
B[i][j] = 1
elif v2 == v and dir == DIRECTION_TO:
B[i][j] = 1
def buildBMatrix(self):
'''
构造关联矩阵
'''
m = len(self.veterxs)
n = len(self.edges)
B = _np.zeros((m, n))
revedges = self.buildrevedges()
for i in range(m):
v = self.veterxs[i]
for j in range(n):
edge = self.edges[j]
if type(edge) is Edge:
v1, v2, dir = edge.vertex1, edge.vertex2, edge.dir
else:
v1, v2, dir = edge
self.__buildBMatrix(B, v, i, j, v1, v2, dir)
for j in range(n):
v1, v2, dir = revedges[j]
self.__buildBMatrix(B, v, i, j, v1, v2, dir)
return _np.matrix(B)
def contains_uni_link(self):
'''
确定有向图`G=(V,E)`是否包含一个通用的汇(入度为|V|-1,出度为0的点)
'''
n = len(self.veterxs)
m = self.matrix
for i in range(n):
if sum(m[i]) == n - 1:
return True
return False
@property
def has_cycle(self):
'''
判断图是否有环路
'''
return hascircuit(self)
@property
def vertex_num(self):
'''
返回图中顶点数量
'''
return len(self.veterxs)
@property
def edge_num(self):
'''
返回图中边的数量
'''
return len(self.edges)
def bfs(g : Graph, s : Vertex):
'''
广度优先搜索(breadth-first search) 时间复杂度`O(V+E)`
Args
===
`g` : type:`Graph`,图`G(V,E)`(无向图或者有向图均可)
`s` : type:`Vertex`,搜索的起点顶点
Return
===
None
Example
===
```python
from graph import *
g = Graph()
v = [Vertex('a'), Vertex('b'), Vertex('c'), Vertex('d'), Vertex('e')]
g.veterxs = v
g.edges.append(Edge(v[0], v[1]))
g.edges.append(Edge(v[0], v[2]))
g.edges.append(Edge(v[1], v[3]))
g.edges.append(Edge(v[2], v[1]))
g.edges.append(Edge(v[3], v[0]))
g.edges.append(Edge(v[4], v[3]))
print('邻接表为')
print(g.adj)
print('邻接矩阵为')
print(g.matrix)
for i in range(len(v)):
bfs(g, v[i])
print('{}到各点的距离为'.format(v[i]))
for u in g.veterxs:
print(u.d, end=' ')
print(' ')
```
'''
g.reset_vertex_para()
adj = g.adj
# g.changeVEToClass()
if type(s) is not Vertex:
key = s
for i in range(len(g.veterxs)):
if g.veterxs[i].key == key:
s = g.veterxs[i]
n = len(g.veterxs)
for i in range(n):
u = g.veterxs[i]
if type(u) is Vertex:
u.color = COLOR_WHITE
u.d = _math.inf
u.pi = None
else:
return
s.color = COLOR_GRAY
s.d = 0
s.pi = None
q = []
q.append(s)
while len(q) != 0:
u = q.pop(0)
uindex = 0
for i in range(n):
if g.veterxs[i].key == u.key:
uindex = i
for i in range(len(adj[uindex])):
v = adj[uindex][i]
if v.color == COLOR_WHITE:
v.color = COLOR_GRAY
v.d = u.d + 1
v.pi = u
q.append(v)
u.color = COLOR_BLACK
class _DFS:
def __init__(self):
self.__adj = []
self.__sort_list = []
self.__time = 0
self.__n = 0
self.__count = 0
self.__scc_count = 0
self.__scc_list = []
def search_path(self, g: Graph, u: Vertex, k : Vertex):
'''
寻找图`g`中顶点`u`到`k`的路径
'''
uindex = 0
for i in range(self.__n):
if g.veterxs[i].key == u.key:
uindex = i
break
for i in range(len(self.__adj[uindex])):
v = self.__adj[uindex][i]
if v.key == k.key:
self.__count += 1
else:
self.search_path(g, v, k)
def dfs_visit_non_recursive(self, g: Graph, u : Vertex):
'''
深度优先搜索从某个顶点开始(非递归)
'''
stack = []
stack.append(u)
self.__time += 1
u.d = self.__time
while len(stack) > 0:
w = stack.pop(0)
w.color = COLOR_GRAY
uindex = 0
for i in range(self.__n):
if g.veterxs[i].key == w.key:
uindex = i
break
for i in range(len(self.__adj[uindex])):
v = self.__adj[uindex][i]
if v.color == COLOR_WHITE:
v.pi = w
stack.append(v)
self.__time += 1
v.d = self.__time
w.color = COLOR_BLACK
self.__time += 1
w.f = self.__time
u.color = COLOR_BLACK
self.__time += 1
u.f = self.__time
def dfs_visit(self, g: Graph, u: Vertex):
'''
深度优先搜索从某个顶点开始
'''
u.color = COLOR_GRAY
self.__time += 1
u.d = self.__time
uindex = 0
for i in range(self.__n):
if g.veterxs[i].key == u.key:
uindex = i
break
for i in range(len(self.__adj[uindex])):
v = self.__adj[uindex][i]
if v.color == COLOR_WHITE:
v.pi = u
self.dfs_visit(g, v)
u.color = COLOR_BLACK
self.__time += 1
u.f = self.__time
self.__sort_list.append(u)
def dfs(self, g: Graph):
'''
深度优先搜索算法(depth-first search) 时间复杂度`Θ(V+E)`
Args
===
`g` : type:`Graph`,图`G(V,E)`(无向图或者有向图均可)
Return
===
None
Example
===
```python
```
'''
self.__adj = g.adj
self.__n = len(g.veterxs)
self.__time = 0
self.__sort_list.clear()
for i in range(self.__n):
u = g.veterxs[i]
u.color = COLOR_WHITE
u.pi = None
for i in range(self.__n):
u = g.veterxs[i]
if u.color == COLOR_WHITE:
self.dfs_visit(g, u)
def topological_sort(self, g: Graph):
'''
拓扑排序 时间复杂度`Θ(V+E)`
Args
===
`g` : type:`Graph`,图`G(V,E)`(无向图)
Return
===
`list` : list 排序好的顶点序列
Example
===
```python
import graph as _g
g = _g.Graph()
g.vertexs = ...
g.edges = ...
topological_sort(g)
```
'''
self.__sort_list.clear()
self.dfs(g)
sort_list = self.__sort_list
return sort_list
def getpathnum_betweentwovertex(self, g: Graph, v1: Vertex, v2: Vertex):
'''
获取有向无回路图`g`中两个顶点`v1`和`v2`之间的路径数目 时间复杂度`Θ(V+E)`
'''
if g.hasdirection() == False:
print('para g 是无向图,不返回路径')
return 0
count = 0
g.reset_vertex_para()
adj = g.adj
n = len(g.veterxs)
if type(v1) is not Vertex:
key = v1
for i in range(len(g.veterxs)):
if g.veterxs[i].key == key:
v1 = g.veterxs[i]
if type(v2) is not Vertex:
key = v2
for i in range(len(g.veterxs)):
if g.veterxs[i].key == key:
v2 = g.veterxs[i]
self.__count = 0
self.__adj = g.adj
self.__n = len(g.veterxs)
self.__time = 0
self.search_path(g, v1, v2)
return self.__count
def scc(self, g : Graph):
'''
获取图`g`的强连通分支 时间复杂度`Θ(V+E)`
'''
self.__scc_count = 0
self.__scc_list.clear()
n = len(g.veterxs)
g.reset_vertex_para()
list = self.topological_sort(g)
self.__scc_count += 1
g_rev = g.gettranspose()
g_rev.reset_vertex_para()
self.dfs(g_rev)
return self.__scc_list, self.__scc_count
__dfs_instance = _DFS()
# 深度优先搜索
dfs = __dfs_instance.dfs
# 拓扑排序
topological_sort = __dfs_instance.topological_sort
# 获得有向无环图的两个顶点间的路径个数
getpathnum_betweentwovertex = __dfs_instance.getpathnum_betweentwovertex
# 强连通分支图
scc = __dfs_instance.scc
def hascircuit_vertex(g: Graph, v : Vertex):
'''
判断一个无向图`g`中顶点`v`是否包含连接自己的回路
'''
stack = []
stack.append(v)
while len(stack) > 0:
stack_v = stack.pop(0)
v_adj = g.getvertexadj(stack_v)
stack_v.color = COLOR_GRAY
for i in range(len(v_adj)):
v_next = v_adj[i]
if v_next.color == COLOR_WHITE:
v_next.pi = stack_v
stack.append(v_next)
if v_next.key == v.key and stack_v.pi is not None and stack_v.pi.key != v.key:
return True
stack_v.color = COLOR_BLACK
return False
def hascircuit(g : Graph):
'''
判断一个无向图`g`中是否包含回路 时间复杂度`O(V)`
'''
n = len(g.veterxs)
result = False
for i in range(n):
v = g.veterxs[i]
g.reset_vertex_para()
result = result or hascircuit_vertex(g, v)
if result == True:
return True
return result
def print_path(g : Graph, s : Vertex, v : Vertex):
'''
输出图`g`中顶点`s`到`v`的最短路径上的所有顶点
'''
g.reset_vertex_para()
bfs(g, s)
if type(s) is not Vertex:
key = s
for i in range(len(g.veterxs)):
if g.veterxs[i].key == key:
s = g.veterxs[i]
if type(v) is not Vertex:
key = v
for i in range(len(g.veterxs)):
if g.veterxs[i].key == key:
v = g.veterxs[i]
if v == s:
print('{}→'.format(s.key), end='')
elif v.pi == None:
print('no path from {} to {} exists'.format(s.key, v.key))
else:
print_path(g, s, v.pi)
print('{}→'.format(v.key), end='')
def undirected_graph_test():
'''
测试无向图
'''
g = Graph()
g.veterxs = ['a', 'b', 'c', 'd', 'e', 'f', 'g']
g.edges = [('a', 'b'), ('a', 'c'), ('b', 'd'),
('b', 'e'), ('c', 'f'), ('c', 'g')]
print('邻接表为')
g.printadj()
print('邻接矩阵为')
print(g.matrix)
def directed_graph_test():
'''
测试有向图
'''
g = Graph()
g.veterxs = ['1', '2', '3', '4', '5', '6']
g.edges = [('1', '2', '→'), ('4', '2', '→'),
('1', '4', '→'), ('2', '5', '→'),
('3', '6', '→'), ('3', '5', '→'),
('5', '4', '→'), ('6', '6', '→')]
print('邻接表为')
print(g.adj)
print('邻接矩阵为')
print(g.matrix)
B = g.buildBMatrix()
print('关联矩阵为')
print(B)
print(B * B.T)
print('是否包含通用的汇', g.contains_uni_link())
def test_bfs():
'''
测试广度优先搜索方法
'''
g = Graph()
v = [Vertex('a'), Vertex('b'), Vertex('c'), Vertex('d'), Vertex('e')]
g.veterxs = v
g.edges.clear()
g.edges.append(Edge(v[0], v[1]))
g.edges.append(Edge(v[0], v[2]))
g.edges.append(Edge(v[1], v[3]))
g.edges.append(Edge(v[2], v[1]))
g.edges.append(Edge(v[3], v[0]))
g.edges.append(Edge(v[4], v[3]))
print('邻接表为')
print(g.adj)
print('邻接矩阵为')
print(g.matrix)
for i in range(len(v)):
bfs(g, v[i])
print('{}到各点的距离为'.format(v[i]))
for u in g.veterxs:
print(u.d, end=' ')
print(' ')
bfs(g, v[0])
print_path(g, v[0], v[4])
print('')
del g
gwithdir = Graph()
vwithdir = [Vertex('a'), Vertex('b'), Vertex('c'),
Vertex('d'), Vertex('e')]
gwithdir.veterxs = vwithdir
gwithdir.edges.clear()
gwithdir.edges.append(Edge(vwithdir[0], vwithdir[1], 1, DIRECTION_TO))
gwithdir.edges.append(Edge(vwithdir[1], vwithdir[2], 1, DIRECTION_TO))
gwithdir.edges.append(Edge(vwithdir[2], vwithdir[3], 1, DIRECTION_TO))
gwithdir.edges.append(Edge(vwithdir[3], vwithdir[4], 1, DIRECTION_TO))
gwithdir.edges.append(Edge(vwithdir[0], vwithdir[2], 1, DIRECTION_TO))
gwithdir.edges.append(Edge(vwithdir[2], vwithdir[4], 1, DIRECTION_TO))
print('邻接表为')
print(gwithdir.adj)
print('邻接矩阵为')
print(gwithdir.matrix)
for i in range(len(vwithdir)):
bfs(gwithdir, vwithdir[i])
print('{}到各点的距离为'.format(vwithdir[i]))
for u in gwithdir.veterxs:
print(u.d, end=' ')
print('')
bfs(gwithdir, vwithdir[0])
print_path(gwithdir, vwithdir[0], vwithdir[4])
print('')
del gwithdir
def test_dfs():
'''
测试深度优先搜索方法
'''
gwithdir = Graph()
vwithdir = [Vertex('a'), Vertex('b'), Vertex('c'),
Vertex('d'), Vertex('e')]
gwithdir.veterxs = vwithdir