std::mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::seed

void seed( result_type value = default_seed );	(1)	(since C++11)
template< class SeedSeq > void seed( SeedSeq& seq );	(2)	(since C++11)

Sets the state of the random-number engine.

1) Right after the state is set, *this == std::mersenne_twister_engine(value) is true.

2) Right after the state is set, *this == std::mersenne_twister_engine(seq) is true.

Parameters

value	-	seed value to use to set the state
seq	-	seed sequence to use to set the state

Exceptions

2) If SeedSeq is not std::seed_seq, throws the exceptions thrown by the seq.generate call.

Complexity

1) Same as std::mersenne_twister_engine(value).

2) Same as std::mersenne_twister_engine(seq).

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2181	C++11	overload (2) would not throw even if the `seq.generate` call throws	propagates the exception

Example

#include <iostream>
#include <random>

int main()
{
    std::mt19937 gen;

    // Seed the engine with an unsigned int
    gen.seed(1);
    std::cout << "after seed by 1: " << gen() << '\n';

    // Seed the engine with two unsigned ints
    std::seed_seq sseq{1, 2};
    gen.seed(sseq);
    std::cout << "after seed by {1,2}: " << gen() << '\n';
}

Possible output:

after seed by 1: 1791095845
after seed by {1,2}: 3127717181