However, if you modify the area of the tree that contains the node receiving the event, the events that you receive and the impact to the tree are undefined.

但如果修改的区域属于包含正接收该事件的节点的树，则接收的事件和对树的影响是不确定的。

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In the undefined northern part of the frontier India claims an area the size of Switzerland, occupied by China, for its region of Ladakh.

ECONOMIST: India and China

It's a new approach to an area of international trade that is still largely undefined.

FORBES: Magazine Article