public member function
<random>

std::random_device::operator()

result_type operator()();
Generate random number
Returns a new random number.

Parameters

None

Return value

A new random number.
result_type is a member type, defined as an alias of unsigned int.

Example

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// random_device example
#include <iostream>
#include <random>

int main ()
{
  std::random_device rd;

  std::cout << "default random_device characteristics:" << std::endl;
  std::cout << "minimum: " << rd.min() << std::endl;
  std::cout << "maximum: " << rd.max() << std::endl;
  std::cout << "entropy: " << rd.entropy() << std::endl;
  std::cout << "a random number: " << rd() << std::endl;

  return 0;
}


Possible output:
default random_device characteristics:
minimum: 0
maximum: 4294967295
entropy: 32
a random number: 3286206242

See also

random_device::random_device
Construct random device (public member function)
random_device::max
Maximum value (public static member function)

C++