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Merge pull request #148 from b1o0d4x3/master

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There were 2 codes for BFS and DFS in data-structure/Graph.
This commit is contained in:
Anup Kumar Panwar 2017-10-07 09:46:38 +05:30 committed by GitHub
commit 3ecb193ae6
2 changed files with 0 additions and 122 deletions
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61
data_structures/Graph/P01_BreadthFirstSearch.py
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@ -1,61 +0,0 @@
# Author: OMKAR PATHAK
class Graph():
def __init__(self):
self.vertex = {}
# for printing the Graph vertexes
def printGraph(self):
for i in self.vertex.keys():
print(i,' -> ', ' -> '.join([str(j) for j in self.vertex[i]]))
# for adding the edge beween two vertexes
def addEdge(self, fromVertex, toVertex):
# check if vertex is already present,
if fromVertex in self.vertex.keys():
self.vertex[fromVertex].append(toVertex)
else:
# else make a new vertex
self.vertex[fromVertex] = [toVertex]
def BFS(self, startVertex):
# Take a list for stoting already visited vertexes
visited = [False] * len(self.vertex)
# create a list to store all the vertexes for BFS
queue = []
# mark the source node as visited and enqueue it
visited[startVertex] = True
queue.append(startVertex)
while queue:
startVertex = queue.pop(0)
print(startVertex, end = ' ')
# mark all adjacent nodes as visited and print them
for i in self.vertex[startVertex]:
if visited[i] == False:
queue.append(i)
visited[i] = True
if __name__ == '__main__':
g = Graph()
g.addEdge(0, 1)
g.addEdge(0, 2)
g.addEdge(1, 2)
g.addEdge(2, 0)
g.addEdge(2, 3)
g.addEdge(3, 3)
g.printGraph()
print('BFS:')
g.BFS(2)
# OUTPUT:
# 0  ->  1 -> 2
# 1  ->  2
# 2  ->  0 -> 3
# 3  ->  3
# BFS:
# 2 0 3 1

61
data_structures/Graph/P02_DepthFirstSearch.py
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@ -1,61 +0,0 @@
# Author: OMKAR PATHAK
class Graph():
def __init__(self):
self.vertex = {}
# for printing the Graph vertexes
def printGraph(self):
print(self.vertex)
for i in self.vertex.keys():
print(i,' -> ', ' -> '.join([str(j) for j in self.vertex[i]]))
# for adding the edge beween two vertexes
def addEdge(self, fromVertex, toVertex):
# check if vertex is already present,
if fromVertex in self.vertex.keys():
self.vertex[fromVertex].append(toVertex)
else:
# else make a new vertex
self.vertex[fromVertex] = [toVertex]
def DFS(self):
# visited array for storing already visited nodes
visited = [False] * len(self.vertex)
# call the recursive helper function
for i in range(len(self.vertex)):
if visited[i] == False:
self.DFSRec(i, visited)
def DFSRec(self, startVertex, visited):
# mark start vertex as visited
visited[startVertex] = True
print(startVertex, end = ' ')
# Recur for all the vertexes that are adjacent to this node
for i in self.vertex.keys():
if visited[i] == False:
self.DFSRec(i, visited)
if __name__ == '__main__':
g = Graph()
g.addEdge(0, 1)
g.addEdge(0, 2)
g.addEdge(1, 2)
g.addEdge(2, 0)
g.addEdge(2, 3)
g.addEdge(3, 3)
g.printGraph()
print('DFS:')
g.DFS()
# OUTPUT:
# 0  ->  1 -> 2
# 1  ->  2
# 2  ->  0 -> 3
# 3  ->  3
# DFS:
# 0 1 2 3