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std::mersenne_twister_engine::mersenne_twister_engine

explicit mersenne_twister_engine( result_type value = default_seed );	(1)	(since C++11)
template< class Sseq > explicit mersenne_twister_engine( Sseq& s );	(2)	(since C++11)
mersenne_twister_engine( const mersenne_twister_engine& );	(3)	(since C++11) (implicitly declared)

Constructs the pseudo-random number engine.

1) Constructs the engine and initializes the state (n values X
i of type result_type) as follows: value mod 2w
is used to initialize X
0 and the rest are initialized iteratively, for i=1-n,...,-1, each X
i is initialized to [f·(X
i-1xor(X
i-1rshift(w-2)))+i mod n] mod 2w

2) Constructs the engine and initializes the state by calling s.generate(a, a+n*k) where a is an array of length n*k and k is ceil(w/32) and then, iteratively for i=-n,...,-1, setting each element of the engine state X
i to (Σk-1
j=0a
k(i+n)+j}·232j
) mod 2w
, and finally if the most significant w-r bits of X
0 are zero, and if all other X
i are zero, replacing X
0 with 2w-1
.

Note: initialization requirements are based on the 2002 version of Mersenne Twister, mt19937ar.c.

The overload (2) only participates in overload resolution if Sseq qualifies as a SeedSequence. In particular, it is excluded from the set of candidate functions if Sseq is convertible to result_type.

Parameters

value	-	seed value to use in the initialization of the internal state
s	-	seed sequence to use in the initialization of the internal state

Complexity

linear in n (the state size).

std::mersenne_twister_engine::mersenne_twister_engine