I can certainly try to write the number 13 there, but bam, my program very likely will crash if this chunk of memory was not given to me previously by the operating system and maybe it is owned by the operating system.

我当然可以在那里写下数字13，但是“嘣“,如果这块内存不是系统预先给我的,我的程序很可能会崩溃,可能这块内存,是系统本身使用的。

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