2021-11-05 19:45:01 +00:00
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= Depth First Search =
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2021-11-06 19:00:01 +00:00
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Depth 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. Depth first search can also be thought of as a
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type of prefix traversal
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== Algorithm ==
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=== Tree ===
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The algorithm is often implemented as a recursive function. For each node in
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the graph, the function checks if the node's value is the desired value, and if
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not immediately calls itself upon that nodes children. Due to this the
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algorithm searches as deeply as possible first and foremost, before then
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searching the width of the tree.
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=== Graph ===
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Graph traversal is similar, however a list of of visited nodes is required.
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This is to ensure that we do not get stuck in loops.
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