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= Breadth First Search =
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Breadth First Search is an algorithm for searching a tree/graph for a node that
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has a certain property. It starts at some chosen/implied root node, and
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traverses the entire tree/graph. Therefore, BFS is often performed in O(|V| +
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|E|) time.
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== Algorithm ==
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=== Tree ===
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The algorithm first starts by creating a Queue, Q, and a pointer to the current
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node, curr. Starting at the root of the tree, all child nodes of the current
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node are placed onto Q, then curr is changed to the first element of Q, which
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is dequeued. This will traverse the tree from left to right, layer by layer. If
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desired, a condition can be added for the desired node.
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This method of traversal *does not* take advantage of the structure of a tree,
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and therefore does not have any of the lookup advantages of a [[binary_tree]].
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=== Graph ===
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Graph traversal is similar, however a list of visited nodes is required. This
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is to ensure that we do not get stuck in loops
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