seeding default_random_engine?

Question

I\'m using visual studio 2010 which doesn\'t support , so I have to seed default_random_engine. Thus, I\'ve decided to seed it with <

Answer 1

I recommend grabbing a seed from std::random_device:

std::default_random_engine engine(std::random_device{}());

which should provide you with significantly more entropy than std::time.

Answer 2

According to http://www.cplusplus.com/reference/random/random_device/, they recommend that you don't use std::random_device, as it isn't portable:

Notice that random devices may not always be available to produce random numbers (and in some systems, they may even never be available).

On a related page (http://www.cplusplus.com/reference/random/linear_congruential_engine/linear_congruential_engine/), they give the following as an example of creating a seed:

unsigned seed1 = std::chrono::system_clock::now().time_since_epoch().count();