在 C++ 应用程序中，我应该多久调用一次 srand()?
我有一个 C++ 应用程序，它在不同的地方调用 rand().我是否需要定期初始化 srand() 以确保 rand() 是合理随机的，还是在应用程序启动时调用一次就足够了?
I have a C++ application which calls rand() in various places. Do I need to initialize srand() regularly to ensure that rand() is reasonably random, or is it enough to call it once when the app starts?
推荐答案
如果您只有一个线程，请一次.如果您经常重新播种，实际上可能会破坏随机数的某些统计特性.如果您有多个线程，则根本不要使用 rand，而是使用诸如 drand48_r 之类的线程安全的东西，它可以让您保持每个线程的状态(因此您可以播种一次每个线程).
If you have only a single thread, seed once. If you reseed often, you might actually break some of the statistical properties of the random numbers. If you have multiple threads, don't use rand at all, but rather something threadsafe like drand48_r, which lets you maintain a per-thread state (so you can seed once per thread).
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