# Can DFS be iterative?

## Can DFS be iterative?

Iterative Implementation of DFS It uses a stack instead of a queue. The DFS should mark discovered only after popping the vertex, not before pushing it. It uses a reverse iterator instead of an iterator to produce the same results as recursive DFS.

### How is DFS iterative implemented?

Algorithm:

1. Created a stack of nodes and visited array.
2. Insert the root in the stack.
3. Run a loop till the stack is not empty.
4. Pop the element from the stack and print the element.
5. For every adjacent and unvisited node of current node, mark the node and insert it in the stack.

What is DFS in data structure?

Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures.

What is DFS in Java?

Depth-first search (DFS) is a traversal algorithm used for both Tree and Graph data structures. The depth-first search goes deep in each branch before moving to explore another branch.

## Does DFS have to be recursive?

The DFS algorithm is a recursive algorithm that uses the idea of backtracking. It involves exhaustive searches of all the nodes by going ahead, if possible, else by backtracking. However, ensure that the nodes that are visited are marked. This will prevent you from visiting the same node more than once.

### What kind of stack is used in iterative DFS?

In the post, iterative DFS is discussed. The recursive implementation uses function call stack. In iterative implementation, an explicit stack is used to hold visited vertices. Below is implementation of Iterative DFS.

What’s the difference between iterative DFS and recursive DFS?

The only difference between iterative DFS and recursive DFS is that the recursive stack is replaced by a stack of nodes. Created a stack of nodes and visited array.

What is the time complexity of iterative DFS?

Implementation of Iterative DFS: This is similar to BFS, the only difference is queue is replaced by stack. Time complexity: O (V + E), where V is the number of vertices and E is the number of edges in the graph. Space Complexity: O (V).

## How are neighbors iterated in a DFS traversal?

The neighbors are iterated through in alphabetical order. For a DFS traversal (the one with a stack, not sure if its recursive or iterative) this is what I got: A, C, D, E, F. Can someone confirm what type of DFS traversal this is, and how the other one would work?