trie的用法

The Entry type, which is used to store the key-value mapping, extends WeakReference, so when expungeStaleEntries() asks for the next expired weak reference, it gets back an Entry.

用于存储键-值映射的Entry类型扩展了WeakReference，因此当expungeStaleEntries（）要求下一个失效的弱引用时，它得到一个Entry。

And in the past the Organization of the Petroleum Exporting Countries, known as OPEC, has frequently cut production to firm up prices.

在过去，石油输出国组织（Organization Of The Petroleum Exporting Countries，简称欧佩克）经常削减原油产量来稳定价格。

Three leading energy agencies recently said production from outside the Organization of the Petroleum Exporting Countries would increase this year, much of it from U.S. shale.

三大能源机构近期表示，今年石油输出国组织（Organization of the Petroleum Exporting Countries，简称：欧佩克）以外国家的原油产量将增加，其中大部分来自美国的页岩油。