mirror of https://github.com/aziis98/asd-2024.git
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
104 lines
2.7 KiB
Python
104 lines
2.7 KiB
Python
# code
|
|
import random
|
|
|
|
|
|
class Graph:
|
|
# instance variables
|
|
def __init__(self, v):
|
|
# v is the number of nodes/vertices
|
|
self.time = 0
|
|
self.traversal_array = []
|
|
self.v = v
|
|
# e is the number of edge (randomly chosen between 9 to 45)
|
|
self.e = random.randint(9, 45)
|
|
# adj. list for graph
|
|
self.graph_list = [[] for _ in range(v)]
|
|
# adj. matrix for graph
|
|
self.graph_matrix = [[0 for _ in range(v)] for _ in range(v)]
|
|
|
|
# function to create random graph
|
|
def create_random_graph(self):
|
|
# add edges upto e
|
|
for i in range(self.e):
|
|
# choose src and dest of each edge randomly
|
|
src = random.randrange(0, self.v)
|
|
dest = random.randrange(0, self.v)
|
|
# re-choose if src and dest are same or src and dest already has an edge
|
|
while src == dest and self.graph_matrix[src][dest] == 1:
|
|
src = random.randrange(0, self.v)
|
|
dest = random.randrange(0, self.v)
|
|
# add the edge to graph
|
|
self.add_edge(src, dest)
|
|
|
|
def add_edge(self, src, dest):
|
|
self.graph_list[src].append(dest)
|
|
self.graph_matrix[src][dest] = 1
|
|
|
|
# function to print adj list
|
|
def print_graph_list(self):
|
|
print("Adjacency List Representation:")
|
|
for i in range(self.v):
|
|
print(i, "-->", *self.graph_list[i])
|
|
print()
|
|
|
|
# function to print adj matrix
|
|
def print_graph_matrix(self):
|
|
print("Adjacency Matrix Representation:")
|
|
for i in self.graph_matrix:
|
|
print(i)
|
|
print()
|
|
|
|
# function the get number of edges
|
|
def number_of_edges(self):
|
|
return self.e
|
|
|
|
# function for dfs
|
|
def dfs(self):
|
|
self.visited = [False]*self.v
|
|
self.start_time = [0]*self.v
|
|
self.end_time = [0]*self.v
|
|
|
|
for node in range(self.v):
|
|
if not self.visited[node]:
|
|
self.traverse_dfs(node)
|
|
print()
|
|
print("DFS Traversal: ", self.traversal_array)
|
|
print()
|
|
|
|
def traverse_dfs(self, node):
|
|
self.visited[node] = True
|
|
self.traversal_array.append(node)
|
|
self.start_time[node] = self.time
|
|
self.time += 1
|
|
for neighbour in self.graph_list[node]:
|
|
print('Edge:', str(node)+'-->'+str(neighbour))
|
|
|
|
if not self.visited[neighbour]:
|
|
print(' => Tree Edge')
|
|
self.traverse_dfs(neighbour)
|
|
else:
|
|
print(f"Times: ({self.start_time[node]}, {self.end_time[node]}) ({self.start_time[neighbour]}, {self.end_time[neighbour]})")
|
|
|
|
if self.start_time[node] > self.start_time[neighbour] and self.end_time[node] < self.end_time[neighbour]:
|
|
print(' => Back Edge')
|
|
elif self.start_time[node] < self.start_time[neighbour] and self.end_time[node] > self.end_time[neighbour]:
|
|
print(' => Forward Edge')
|
|
else:
|
|
print(' => Cross Edge')
|
|
self.end_time[node] = self.time
|
|
self.time += 1
|
|
|
|
|
|
if __name__ == "__main__":
|
|
g = Graph(4)
|
|
# g.create_random_graph()
|
|
|
|
g.add_edge(0, 1)
|
|
g.add_edge(1, 2)
|
|
g.add_edge(2, 3)
|
|
g.add_edge(3, 1)
|
|
|
|
g.print_graph_list()
|
|
g.print_graph_matrix()
|
|
g.dfs()
|