# Edge-Classification In DIrected Graph using BFS

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In BFS of a directed graph, we don't have forward edges.Only tree edge,cross edge or back edge.

Below is a sample graph I have taken and classified edge types.

Please verify guys whether it's correct.

The algorithm I have used is the pseudocode given by "redtuna" in the selected answer here. 0
i didn't understood the algo given in the link, but as per me the classification which you did, is correct
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@Shaik  and @Ayush

why BFS no need of forward edges?
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mam, if it is a forward edge present , then it will recognize as tree edge at first step only !
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Shaik Masthan plzz ellaborate ur line

mam, if it is a forward edge present , then it will recognize as tree edge at first step only

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Recognition of forward edge requires say for a Edge A->B, B should have been visited before the edge A-B is discovered and this can happen only when B is visited via some other vertex using more than one edge.Since, BFS finds shortest path from source in terms of smaller number of edges, When Vertex A is enqueued, edge A-B will be discovered and marked a tree or cross edge.Hence forward edges never possible.
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What is forward edge? Let there is a tree edge between A to B and B to C then A --> C is a forward edge, think  that At A itself C is pushed into queue then there is no chance of A --> C is look as forward edge

## Related questions

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Consider the following statements: 1. Let T be the DFS tree resulting from DFS traversal on a connected directed graph the root of the tree is an articulation point, iff it has at least two children. 2. When BFS is carried out on a directed graph G, the edges of G will ... as tree edge, back edge, or cross edge and not forward edge as in the case of DFS. Find TRUE or FALSE for both the statements