Defined in header <random> | ||
---|---|---|
class seed_seq; | (since C++11) |
std::seed_seq
consumes a sequence of integer-valued data and produces a requested number of unsigned integer values i
, 0 ≤ i < 232
, based on the consumed data. The produced values are distributed over the entire 32-bit range even if the consumed values are close.
It provides a way to seed a large number of random number engines or to seed a generator that requires a lot of entropy, given a small seed or a poorly distributed initial seed sequence.
std::seed_seq
meets the requirements of SeedSequence.
Member type | Definition |
---|---|
result_type | std::uint_least32_t |
constructs and seeds the std::seed_seq object (public member function) |
|
operator=
(deleted) | not copy-assignable (public member function) |
calculates the bias-eliminated, evenly distributed 32-bit values (public member function) |
|
obtains the number of 32-bit values stored in std::seed_seq (public member function) |
|
obtains the 32-bit values stored in std::seed_seq (public member function) |
#include <random> #include <cstdint> #include <iostream> int main() { std::seed_seq seq{1,2,3,4,5}; std::vector<std::uint32_t> seeds(10); seq.generate(seeds.begin(), seeds.end()); for (std::uint32_t n : seeds) { std::cout << n << '\n'; } }
Output:
4204997637 4246533866 1856049002 1129615051 690460811 1075771511 46783058 3904109078 1534123438 1495905678
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