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# Python3 program to print DFS traversal |
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from collections import defaultdict |
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# This class represents a directed graph using |
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# adjacency list representation |
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class Graph: |
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# Constructor |
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def __init__(self): |
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# default dictionary to store graph |
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self.graph = defaultdict(list) |
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# function to add an edge to graph |
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def addEdge(self, u, v): |
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self.graph[u].append(v) |
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# A function used by DFS |
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def DFSUtil(self, v, visited): |
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# Mark the current node as visited |
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# and print it |
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visited[v] = True |
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print(v, end = ' ') |
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# Recur for all the vertices |
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# adjacent to this vertex |
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for i in self.graph[v]: |
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if visited[i] == False: |
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self.DFSUtil(i, visited) |
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# The function to do DFS traversal. It uses |
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# recursive DFSUtil() |
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def DFS(self, v): |
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# Mark all the vertices as not visited |
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visited = [False] * (len(self.graph)) |
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# Call the recursive helper function |
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# to print DFS traversal |
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self.DFSUtil(v, visited) |
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# Driver code |
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# Create a graph given |
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# in the above diagram |
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g = Graph() |
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g.addEdge(0, 1) |
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g.addEdge(0, 2) |
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g.addEdge(1, 2) |
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g.addEdge(2, 0) |
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g.addEdge(2, 3) |
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g.addEdge(3, 3) |
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print("Following is DFS from (starting from vertex 2)") |
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g.DFS(2) |
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