"""
参考链接
DFS 代码模板（递归写法、非递归写法） https://shimo.im/docs/ddgwCccJQKxkrcTq/read
BFS 代码模板 https://shimo.im/docs/P8TqKHGKt3ytkYYd/read
"""
# 标准广度优先搜索的终止条件就是找到结束单词。
"""
实战题目
https://leetcode-cn.com/problems/binary-tree-level-order-traversal/#/description
https://leetcode-cn.com/problems/minimum-genetic-mutation/#/description
https://leetcode-cn.com/problems/generate-parentheses/#/description
https://leetcode-cn.com/problems/find-largest-value-in-each-tree-row/#/description
课后作业
https://leetcode-cn.com/problems/word-ladder/description/
https://leetcode-cn.com/problems/word-ladder-ii/description/
https://leetcode-cn.com/problems/number-of-islands/
https://leetcode-cn.com/problems/minesweeper/description/
"""
