深度优先搜索 (Depth-First Search (DFS))

概述

难度：中等 (Medium)
分类：Graph Traversal / 图遍历

深度优先搜索是一种Graph/树遍历算法，沿着一条路径走到底，然后回溯探索其他路径。

DFS is a graph/tree traversal algorithm that explores as far as possible along each branch before backtracking.

算法原理

中文：从起点开始，尽可能深地访问节点，直到没有未访问的邻居，然后回溯。

English: Start from the source, visit nodes as deep as possible, until no unvisited neighbors, then backtrack.

复杂度分析

代码实现

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

每日练习

1. 完成算法实现
2. 分析算法复杂度
3. 思考：算法的适用场景和局限性

相关阅读：算法专栏

💡 学习建议：算法学习重在理解思想，多写多练是关键。 💡 Learning tip: Algorithm learning is about understanding the core idea. Practice makes perfect.