源码如下:
template <class RandomAccessIterator, class Distance>
void __random_shuffle(RandomAccessIterator first, RandomAccessIterator last,
Distance*) {
if (first == last) return;
for (RandomAccessIterator i = first + 1; i != last; ++i)
#ifdef __STL_NO_DRAND48
iter_swap(i, first + Distance(rand() % ((i - first) + 1)));
#else
iter_swap(i, first + Distance(lrand48() % ((i - first) + 1)));
#endif
}
这里的iter_swap(i, first + Distance(rand() % ((i - first) + 1)));能否保证数组是均匀的重排呢?
如何保证?