Definition
Depth First Search (DFS) is a fundamental algorithm used for traversing or searching tree or graph data structures. Starting from an initial node, DFS explores as far as possible along each branch before backtracking, utilizing a stack data structure to manage the traversal process.
Working Principle
- Starting Point: Select a starting node (e.g., node A). This node will be the root of our search.
- Traversal Method: from the starting node, move to one of its neighbors. This is done one neighbor at a time. Use a stack to keep track of the nodes. Each visited node is pushed onto the stack, and once all its neighbors have been visited, it is popped from the stack.
- Recursive Exploration: each node is explored recursively, visiting all reachable neighbors from that node. Ensure that each node is visited only once to avoid cycles and redundant work.
- Completion: The process continues until all nodes have been visited, ensuring the traversal covers the entire graph
Key Considerations
- Each node must be visited exactly once
- Upon completing the traversal, the search should return to the starting node, ensuring all nodes are visited.
Application
- Path finding and maze solving
- dynamic analysis
- Topological sorting in dependency resolution
- Detecting cycles in graphs
- Solving puzzles and games that require exhaustive search
- direct graph-based logic flow analysis