Preorder traversal
[计] 前序遍历
🧩 词语组成解析
[计] 先根次序
[计] 遍历
🗣️ 情景例句
What do you mean?
你是什么意思？
Two things doth prolong your life: a quiet heart and a loving wife.
心情平静妻贤淑，延年益寿多得福。
Fortunately for me, as I was wondering what to do next, there appeared on the horizon a man on horseback, riding in my direction.
不过，我是幸运的，正当我走投无路之时，从天边出现一个骑马的人向我骑来。