What is depth-first search and how can I implement it in Python?

What is depth-first search and how can I implement it in Python?

Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures. In Python, you can implement it using recursion or a stack.

Can you show me a simple example of DFS in Python?

Sure! Here's a simple implementation using recursion:

def dfs(graph, node, visited=None):
    if visited is None:
        visited = set()
    visited.add(node)
    for neighbor in graph[node]:
        if neighbor not in visited:
            dfs(graph, neighbor, visited)
    return visited

What kind of data structure is best for representing the graph?

A common way to represent a graph is using an adjacency list, which can be implemented with a dictionary in Python. Each key is a node, and the value is a list of its neighbors.

Can DFS be used for finding paths in a maze?

Yes, DFS can be used to find paths in a maze by exploring each possible path until it reaches the exit or exhausts all options.