mirror of
https://github.com/TheAlgorithms/Python.git
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4fa8c9d4b4
- update naming style to snake_case - add type hints
66 lines
1.6 KiB
Python
66 lines
1.6 KiB
Python
#!/usr/bin/python
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""" Author: OMKAR PATHAK """
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class Graph:
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def __init__(self):
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self.vertex = {}
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# for printing the Graph vertices
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def print_graph(self) -> None:
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print(self.vertex)
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for i in self.vertex:
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print(i, " -> ", " -> ".join([str(j) for j in self.vertex[i]]))
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# for adding the edge between two vertices
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def add_edge(self, from_vertex: int, to_vertex: int) -> None:
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# check if vertex is already present,
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if from_vertex in self.vertex:
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self.vertex[from_vertex].append(to_vertex)
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else:
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# else make a new vertex
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self.vertex[from_vertex] = [to_vertex]
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def dfs(self) -> None:
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# visited array for storing already visited nodes
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visited = [False] * len(self.vertex)
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# call the recursive helper function
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for i in range(len(self.vertex)):
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if not visited[i]:
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self.dfs_recursive(i, visited)
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def dfs_recursive(self, start_vertex: int, visited: list) -> None:
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# mark start vertex as visited
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visited[start_vertex] = True
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print(start_vertex, end=" ")
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# Recur for all the vertices that are adjacent to this node
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for i in self.vertex:
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if not visited[i]:
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self.dfs_recursive(i, visited)
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if __name__ == "__main__":
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g = Graph()
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g.add_edge(0, 1)
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g.add_edge(0, 2)
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g.add_edge(1, 2)
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g.add_edge(2, 0)
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g.add_edge(2, 3)
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g.add_edge(3, 3)
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g.print_graph()
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print("DFS:")
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g.dfs()
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# OUTPUT:
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# 0 -> 1 -> 2
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# 1 -> 2
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# 2 -> 0 -> 3
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# 3 -> 3
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# DFS:
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# 0 1 2 3
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