The pre order, in order and post order traversal of every binary tree are unique, but those of different binary trees may be identical.

但是不同的二叉树的先序遍历序列或中序遍历序列或后序遍历序列有可能是相同的。

youdao

Apple gave us the answers to two very important questions today — when can you pre-order an iPad and when can you buy one — but left a lot to the imagination.

苹果今天回答了我们两个非常重要的问题——何时可以预定和购买iPad，但是仍为我们留下了很多的想象空间。

youdao

Apple's pre-order press release didn't mention accessories.

Apple的预售新闻稿没有提及配件。

youdao

They made it clear to the former Nigerian military ruler that a return to constitutional order is a pre-condition for direct talks with President Mamadou Tandja.

VOA: standard.2009.11.14

It's instead a process of organizing pre-existing materials And imposing order on those chaotic materials.

相反，它是一个组织原来存在物质的过程,并且给这些混乱的物质赋予秩序。

耶鲁公开课 - 旧约导论课程节选

shuttle cs50 net So if you go back to shuttleboy.cs50.net, you can pre-order for free your own CS50 Shuttle Cards, Shuttle Cards particularly those of you in the Quad, Mather and the like.

如果你去看，你可以免费，提前预定自己的。

哈佛公开课 - 计算机科学课程节选

As an added bonus for consumers, a Chase McCain LEGO minifigure will come as a special pre-order bonus for those who pre-order a copy of LEGO City: Undercover at participating retailers while supplies last.

ENGADGET: Nintendo Wii U arrives in the US on Nov. 18 in two versions for $300 and $350, Europe on Nov. 30

Further, considering the huge pre-order demand for the iPhone 5 (Apple saw twice as many pre-orders for iPhone 5 as the 4S on the launch day), we believe that an increasing number of people are choosing to adopt the pre-order route this time.

FORBES: Overwhelming Pre-Order Demand Could Be The Reason Behind Apple's Disappointing iPhone 5 Sales

The Leap Motion controller will be available for pre-order online at BestBuy.com beginning in February, and Leap Motion will also continue taking pre-orders directly at LeapMotion.com.

FORBES: Leap Motion Makes Exclusive Deal With Best Buy