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Format python codes with black. (#453)

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This commit is contained in:
Yudong Jin
2023-04-09 05:05:35 +08:00
committed by GitHub
parent 1c8b7ef559
commit 5ddcb60825
45 changed files with 656 additions and 456 deletions
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39
codes/python/chapter_graph/graph_adjacency_list.py
View File

@@ -5,13 +5,16 @@ Author: Krahets (krahets@163.com)
"""
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from modules import *
class GraphAdjList:
""" 基于邻接表实现的无向图类 """
"""基于邻接表实现的无向图类"""
def __init__(self, edges: list[list[Vertex]]) -> None:
""" 构造方法 """
"""构造方法"""
# 邻接表，key: 顶点，value：该顶点的所有邻接顶点
self.adj_list = dict[Vertex, Vertex]()
# 添加所有顶点和边
@@ -21,11 +24,11 @@ class GraphAdjList:
self.add_edge(edge[0], edge[1])
def size(self) -> int:
""" 获取顶点数量 """
"""获取顶点数量"""
return len(self.adj_list)
def add_edge(self, vet1: Vertex, vet2: Vertex) -> None:
""" 添加边 """
"""添加边"""
if vet1 not in self.adj_list or vet2 not in self.adj_list or vet1 == vet2:
raise ValueError
# 添加边 vet1 - vet2
@@ -33,7 +36,7 @@ class GraphAdjList:
self.adj_list[vet2].append(vet1)
def remove_edge(self, vet1: Vertex, vet2: Vertex) -> None:
""" 删除边 """
"""删除边"""
if vet1 not in self.adj_list or vet2 not in self.adj_list or vet1 == vet2:
raise ValueError
# 删除边 vet1 - vet2
@@ -41,14 +44,14 @@ class GraphAdjList:
self.adj_list[vet2].remove(vet1)
def add_vertex(self, vet: Vertex) -> None:
""" 添加顶点 """
"""添加顶点"""
if vet in self.adj_list:
return
# 在邻接表中添加一个新链表
self.adj_list[vet] = []
def remove_vertex(self, vet: Vertex) -> None:
""" 删除顶点 """
"""删除顶点"""
if vet not in self.adj_list:
raise ValueError
# 在邻接表中删除顶点 vet 对应的链表
@@ -59,7 +62,7 @@ class GraphAdjList:
self.adj_list[vertex].remove(vet)
def print(self) -> None:
""" 打印邻接表 """
"""打印邻接表"""
print("邻接表 =")
for vertex in self.adj_list:
tmp = [v.val for v in self.adj_list[vertex]]
@@ -68,33 +71,39 @@ class GraphAdjList:
""" Driver Code """
if __name__ == "__main__":
""" 初始化无向图 """
# 初始化无向图
v = vals_to_vets([1, 3, 2, 5, 4])
edges = [[v[0], v[1]], [v[0], v[3]], [v[1], v[2]],
[v[2], v[3]], [v[2], v[4]], [v[3], v[4]]]
edges = [
[v[0], v[1]],
[v[0], v[3]],
[v[1], v[2]],
[v[2], v[3]],
[v[2], v[4]],
[v[3], v[4]],
]
graph = GraphAdjList(edges)
print("\n初始化后，图为")
graph.print()
""" 添加边 """
# 添加边
# 顶点 1, 2 即 v[0], v[2]
graph.add_edge(v[0], v[2])
print("\n添加边 1-2 后，图为")
graph.print()
""" 删除边 """
# 删除边
# 顶点 1, 3 即 v[0], v[1]
graph.remove_edge(v[0], v[1])
print("\n删除边 1-3 后，图为")
graph.print()
""" 添加顶点 """
# 添加顶点
v5 = Vertex(6)
graph.add_vertex(v5)
print("\n添加顶点 6 后，图为")
graph.print()
""" 删除顶点 """
# 删除顶点
# 顶点 3 即 v[1]
graph.remove_vertex(v[1])
print("\n删除顶点 3 后，图为")

29
codes/python/chapter_graph/graph_adjacency_matrix.py
View File

@@ -5,18 +5,21 @@ Author: Krahets (krahets@163.com)
"""
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from modules import *
class GraphAdjMat:
""" 基于邻接矩阵实现的无向图类 """
"""基于邻接矩阵实现的无向图类"""
# 顶点列表，元素代表“顶点值”，索引代表“顶点索引”
vertices: list[int] = []
# 邻接矩阵，行列索引对应“顶点索引”
adj_mat: list[list[int]] = []
def __init__(self, vertices: list[int], edges: list[list[int]]) -> None:
""" 构造方法 """
"""构造方法"""
self.vertices: list[int] = []
self.adj_mat: list[list[int]] = []
# 添加顶点
@@ -28,11 +31,11 @@ class GraphAdjMat:
self.add_edge(e[0], e[1])
def size(self) -> int:
""" 获取顶点数量 """
"""获取顶点数量"""
return len(self.vertices)
def add_vertex(self, val: int) -> None:
""" 添加顶点 """
"""添加顶点"""
n = self.size()
# 向顶点列表中添加新顶点的值
self.vertices.append(val)
@@ -44,7 +47,7 @@ class GraphAdjMat:
row.append(0)
def remove_vertex(self, index: int) -> None:
""" 删除顶点 """
"""删除顶点"""
if index >= self.size():
raise IndexError()
# 在顶点列表中移除索引 index 的顶点
@@ -56,7 +59,7 @@ class GraphAdjMat:
row.pop(index)
def add_edge(self, i: int, j: int) -> None:
""" 添加边 """
"""添加边"""
# 参数 i, j 对应 vertices 元素索引
# 索引越界与相等处理
if i < 0 or j < 0 or i >= self.size() or j >= self.size() or i == j:
@@ -66,7 +69,7 @@ class GraphAdjMat:
self.adj_mat[j][i] = 1
def remove_edge(self, i: int, j: int) -> None:
""" 删除边 """
"""删除边"""
# 参数 i, j 对应 vertices 元素索引
# 索引越界与相等处理
if i < 0 or j < 0 or i >= self.size() or j >= self.size() or i == j:
@@ -75,7 +78,7 @@ class GraphAdjMat:
self.adj_mat[j][i] = 0
def print(self) -> None:
""" 打印邻接矩阵 """
"""打印邻接矩阵"""
print("顶点列表 =", self.vertices)
print("邻接矩阵 =")
print_matrix(self.adj_mat)
@@ -83,7 +86,7 @@ class GraphAdjMat:
""" Driver Code """
if __name__ == "__main__":
""" 初始化无向图 """
# 初始化无向图
# 请注意，edges 元素代表顶点索引，即对应 vertices 元素索引
vertices: list[int] = [1, 3, 2, 5, 4]
edges: list[list[int]] = [[0, 1], [0, 3], [1, 2], [2, 3], [2, 4], [3, 4]]
@@ -91,24 +94,24 @@ if __name__ == "__main__":
print("\n初始化后，图为")
graph.print()
""" 添加边 """
# 添加边
# 顶点 1, 2 的索引分别为 0, 2
graph.add_edge(0, 2)
print("\n添加边 1-2 后，图为")
graph.print()
""" 删除边 """
# 删除边
# 顶点 1, 3 的索引分别为 0, 1
graph.remove_edge(0, 1)
print("\n删除边 1-3 后，图为")
graph.print()
""" 添加顶点 """
# 添加顶点
graph.add_vertex(6)
print("\n添加顶点 6 后，图为")
graph.print()
""" 删除顶点 """
# 删除顶点
# 顶点 3 的索引为 1
graph.remove_vertex(1)
print("\n删除顶点 3 后，图为")

31
codes/python/chapter_graph/graph_bfs.py
View File

@@ -5,13 +5,15 @@ Author: Krahets (krahets@163.com)
"""
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from modules import *
from collections import deque
from graph_adjacency_list import GraphAdjList
def graph_bfs(graph: GraphAdjList, start_vet: Vertex) -> list[Vertex]:
""" 广度优先遍历 BFS """
"""广度优先遍历 BFS"""
# 使用邻接表来表示图，以便获取指定顶点的所有邻接顶点
# 顶点遍历序列
res = []
@@ -22,29 +24,40 @@ def graph_bfs(graph: GraphAdjList, start_vet: Vertex) -> list[Vertex]:
# 以顶点 vet 为起点，循环直至访问完所有顶点
while len(que) > 0:
vet = que.popleft() # 队首顶点出队
res.append(vet) # 记录访问顶点
res.append(vet) # 记录访问顶点
# 遍历该顶点的所有邻接顶点
for adj_vet in graph.adj_list[vet]:
if adj_vet in visited:
continue # 跳过已被访问过的顶点
continue # 跳过已被访问过的顶点
que.append(adj_vet) # 只入队未访问的顶点
visited.add(adj_vet) # 标记该顶点已被访问
visited.add(adj_vet) # 标记该顶点已被访问
# 返回顶点遍历序列
return res
""" Driver Code """
if __name__ == "__main__":
"""初始化无向图"""
# 初始化无向图
v = vals_to_vets([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
edges = [[v[0], v[1]], [v[0], v[3]], [v[1], v[2]], [v[1], v[4]],
[v[2], v[5]], [v[3], v[4]], [v[3], v[6]], [v[4], v[5]],
[v[4], v[7]], [v[5], v[8]], [v[6], v[7]], [v[7], v[8]]]
edges = [
[v[0], v[1]],
[v[0], v[3]],
[v[1], v[2]],
[v[1], v[4]],
[v[2], v[5]],
[v[3], v[4]],
[v[3], v[6]],
[v[4], v[5]],
[v[4], v[7]],
[v[5], v[8]],
[v[6], v[7]],
[v[7], v[8]],
]
graph = GraphAdjList(edges)
print("\n初始化后，图为")
graph.print()
"""广度优先遍历 BFS"""
# 广度优先遍历 BFS
res = graph_bfs(graph, v[0])
print("\n广度优先遍历（BFS）顶点序列为")
print(vets_to_vals(res))

25
codes/python/chapter_graph/graph_dfs.py
View File

@@ -5,24 +5,27 @@ Author: Krahets (krahets@163.com)
"""
import sys, os.path as osp
sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
from modules import *
from graph_adjacency_list import GraphAdjList
def dfs(graph: GraphAdjList, visited: set[Vertex], res: list[Vertex], vet: Vertex):
""" 深度优先遍历 DFS 辅助函数 """
res.append(vet) # 记录访问顶点
visited.add(vet) # 标记该顶点已被访问
"""深度优先遍历 DFS 辅助函数"""
res.append(vet) # 记录访问顶点
visited.add(vet) # 标记该顶点已被访问
# 遍历该顶点的所有邻接顶点
for adjVet in graph.adj_list[vet]:
if adjVet in visited:
continue # 跳过已被访问过的顶点
continue # 跳过已被访问过的顶点
# 递归访问邻接顶点
dfs(graph, visited, res, adjVet)
# 使用邻接表来表示图，以便获取指定顶点的所有邻接顶点
def graph_dfs(graph: GraphAdjList, start_vet: Vertex) -> list[Vertex]:
""" 深度优先遍历 DFS """
"""深度优先遍历 DFS"""
# 顶点遍历序列
res = []
# 哈希表，用于记录已被访问过的顶点
@@ -35,12 +38,18 @@ def graph_dfs(graph: GraphAdjList, start_vet: Vertex) -> list[Vertex]:
if __name__ == "__main__":
# 初始化无向图
v = vals_to_vets([0, 1, 2, 3, 4, 5, 6])
edges = [[v[0], v[1]], [v[0], v[3]], [v[1], v[2]],
[v[2], v[5]], [v[4], v[5]], [v[5], v[6]]]
edges = [
[v[0], v[1]],
[v[0], v[3]],
[v[1], v[2]],
[v[2], v[5]],
[v[4], v[5]],
[v[5], v[6]],
]
graph = GraphAdjList(edges)
print("\n初始化后，图为")
graph.print()
# 深度优先遍历 DFS
res = graph_dfs(graph, v[0])
print("\n深度优先遍历（DFS）顶点序列为")