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