You must be sure that, if you're doing a right rotation, the top node has a left child.

必须要确保，如果做右旋，顶端节点必须有一个左子节点。

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The push method observes the current top node, constructs a new node to be pushed on the stack, and then, if the topmost node has not changed since the initial observation, installs the new node.

push方法观察当前最顶的节点，构建一个新节点放在堆栈上，然后，如果最顶端的节点在初始观察之后没有变化，那么就安装新节点。

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In the genmodel editor, right click on the top node labeled "Mysql" and generate the model Code (see Figure 9), the edit Code (see Figure 10), and finally the Topology edit Code (see Figure 11).

在genmodel编辑器中，右击标为的顶部节点，并生成model代码(见于图9)，Edit代码(见于图10)，以及最终的Topology Edit代码(见于图11)。

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Science editor Alan Boyle's blog: A laser attack on a lymph node provides the drama behind the top-rated video in Nikon's 2012 Small World in Motion competition, which celebrates time-lapse movies made on a microscopic scale.

MSN: Should we have cloned rare tortoise Lonesome George?