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Construct adjacency list by using adjacency matrix in python

Python program for Construct adjacency list by using adjacency matrix. Here problem description and other solutions.

#    Python 3 program for
#    Construct adjacency list using adjacency matrix
class Graph :
	def __init__(self, matrix) :
		#  Set number of nodes
		self.vertices = len(matrix)
		self.adgeList = []
		i = 0
		#  Create memory of adgeList of each vertice
		while (i < self.vertices) :
			self.adgeList.append([])
			i += 1
		
		self.makeAdjacencyList(matrix)
	
	#  Convert into adjacency list
	def makeAdjacencyList(self, matrix) :
		i = 0
		while (i < self.vertices) :
			j = 0
			while (j < self.vertices) :
				if (matrix[i][j] == 1) :
					self.addEdge(i, j)
				
				j += 1
			
			i += 1
		
	
	def addEdge(self, u, v) :
		if (u < 0 or u >= self.vertices or 
            v < 0 or v >= self.vertices) :
			return
		
		#  Add node edge
		self.adgeList[u].append(v)
	
	#  Display graph nodes and edges
	def printGraph(self) :
		print("\n Graph Adjacency List ", end = "")
		i = 0
		while (i < self.vertices) :
			print(" \n [", i ,"] :", end = "", sep = "")
			j = 0
			#  iterate edges of i node
			while (j < len(self.adgeList[i])) :
				if (j != 0) :
					print(" → ", end = "")
				
				print("", self.adgeList[i][j], end = "")
				j += 1
			
			i += 1
		
	

def main() :
	matrix = [
		[0, 1, 1, 0, 1],
		[1, 0, 1, 0, 1],
		[1, 1, 0, 1, 0],
		[0, 1, 0, 0, 1],
		[1, 1, 0, 1, 0]
	]
	g = Graph(matrix)
	#  Display graph element
	g.printGraph()

if __name__ == "__main__": main()

Output

 Graph Adjacency List
 [0] : 1 →  2 →  4
 [1] : 0 →  2 →  4
 [2] : 0 →  1 →  3
 [3] : 1 →  4
 [4] : 0 →  1 →  3




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