C++

Reference

<random>

linear_congruential_engine

public member function
<random>

std::linear_congruential_engine::discard

void discard (unsigned long long z);
Advance internal state
Advances the internal state by z notches, as if operator() was called z times, but without generating any numbers in the process.

The effects on the state sequence are the same as if the transition algorithm was applied as many times as notches advanced:



Where x is the current state value, a and c are their respective class template parameters, and m is its respective class template parameter if this is greater than 0, or numerics_limits<UIntType>::max() plus 1, otherwise.

Parameters

z
Number of equivalent advances.

Return value

None

Example

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// linear_congruential_engine::discard
#include <iostream>
#include <chrono>
#include <random>

int main ()
{
  // obtain a seed from the system clock:
  unsigned seed = std::chrono::system_clock::now().time_since_epoch().count();

  std::minstd_rand0 generator (seed);  // minstd_rand0 is a standard linear_congruential_engine

  std::cout << "Random value: " << generator() << std::endl;

  generator.discard(10);     // discard 10 values

  std::cout << "Random value: " << generator() << std::endl;

  return 0;
}

Possible output:
Random value: 1170275710
Random value: 44925998


Complexity

Linear in z.

See also

linear_congruential_engine::operator()
Generate random number (public member function)