In a reference counting system, each object referenced maintains a count of how many objects are referencing it.

在引用计数系统，每个所引用的对象都会保留一个计数，以获悉有多少对象正在引用它。

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Reference counting involves keeping a count of how many references to a given object are extant, then deleting the object automatically after the last one is released.

引用计数(reference counting)是对一个给定的对象当前有多少指向它的引用保留有一个计数，然后当最后一个引用被释放时自动删除该对象。

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Instance counting is the easiest way of implementing garbage collection. For each reference made to the object the counter is increased, for each release it is decreased.

实例计数是实现垃圾回收的最简单的方法。对每个声明，将会使该对象的计数器增加，每个释放将使其减小。

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