public member function
<random>

std::mersenne_twister_engine::seed

(1)
void seed (result_type val = default_seed);
(2)
template <class Sseq>void seed (Sseq& q);
Seed engine
Re-initializes the internal state sequence to pseudo-random values, either applying a linear random generator on a single value (val) or using a seed sequence object (q) (whose values are transformed).

Parameters

val
A seeding value. An entire state sequence is generated from this value using a linear random generator.
result_type is a member type, defined as an alias of the first class template parameter (UIntType).
default_seed is a member constant, defined as 5489u.
q
A seed sequence object, such as an object of type seed_seq.
Sseq shall be a seed sequence class, with a generate member function.

Return value

None

Example

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// mersenne_twister_engine::seed example
#include <iostream>
#include <chrono>
#include <random>

int main ()
{
  typedef std::chrono::high_resolution_clock myclock;
  myclock::time_point beginning = myclock::now();

  // obtain a seed from a user string:
  std::string str;
  std::cout << "Please, enter a seed: ";
  std::getline(std::cin,str);
  std::seed_seq seed1 (str.begin(),str.end());

  // obtain a seed from the timer
  myclock::duration d = myclock::now() - beginning;
  unsigned seed2 = d.count();

  std::mt19937 generator (seed1);   // mt19937 is a standard mersenne_twister_engine
  std::cout << "Your seed produced: " << generator() << std::endl;

  generator.seed (seed2);
  std::cout << "A time seed produced: " << generator() << std::endl;

  return 0;
}

Possible output:
Please, enter a seed: Matsumoto and Nishimura
Your seed produced: 683129629
A time seed produced: 1889891986


Complexity

Linear on state_size.

See also