To avoid dangling Pointers (the dangerous situation where a block of memory is freed but a pointer still references it), you must delete the object only after the last reference is released.

为了避免悬空指针(一种危险的情况，即一块内存已经被释放了，而一个指针还在引用它)，必须在最后的引用释放之后才删除对象。

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USBQC will help you to remove dangerous applications before it attack your PC via USB memory devices.

USBQC将帮助你去除危险的应用程序之前，它通过USB存储设备攻击你的电脑。

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At best a wistful memory, at worst a dangerous enemy who is in possession of many of your deepest secrets.

最好的能留给你一个情意绵绵的回忆；最糟糕的拥有你的许多机密从而成为你危险的敌人。

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We have a nostalgic conception of good agriculture, a dangerous memory that shrouds the issue in confusion.

WSJ: Dan Barber's Culinary Crusade

The larger lesson is that, when it comes to human memory, more deliberation is often dangerous.

WSJ: Jonah Lehrer on Memory, Witnesses and Crime | Head Case

It can be extremely dangerous for aging parents to rely only on memory when it comes to taking medication.

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