sügavusotsingu

sügavusotsingu, often translated as depth-first search (DFS), is an algorithm for traversing or searching tree or graph data structures. It begins at the root node (or an arbitrary node in the case of a graph) and explores as far as possible along each branch before backtracking. The algorithm prioritizes going deeper into the structure before exploring other branches.

In a tree, DFS systematically visits each node. It moves down a path until it reaches a leaf node, then it backtracks to the previous node and explores the next available branch. This process continues until all nodes have been visited. For graphs, DFS can be used to determine connectivity, find paths, or detect cycles. It can be implemented using recursion or a stack data structure.

When using recursion, the function calls itself for each unvisited neighbor of the current node. With a stack, the algorithm pushes the starting node onto the stack. Then, while the stack is not empty, it pops a node, marks it as visited, and pushes all its unvisited neighbors onto the stack. The order in which neighbors are pushed can determine the specific traversal path.

DFS is particularly useful for problems where the solution is expected to be found deep within the search space. It is also employed in topological sorting, solving mazes, and finding connected components in a graph. Its memory requirement is proportional to the depth of the search, which can be advantageous over breadth-first search in certain scenarios.