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Showing content from https://cplusplus.com/reference/random/bernoulli_distribution/ below:

class

std::bernoulli_distribution

class bernoulli_distribution;

Bernoulli distribution

Random number distribution that produces bool values according to a Bernoulli distribution, which is described by the following probability mass function:

Where the probability of true is p and the probability of false is (1-p).

This represents one of the simplest distribution functions: The tossing of a coin is distributed according to a Bernoulli distribution with a probability p of approximately 0.5.

The distribution parameter, p, is set on construction.

To produce a random value following this distribution, call its member function operator().

Member types The following aliases are member types of bernoulli_distribution:

member type definition notes result_type bool The type of the results generated param_type not specified The type returned by member param.

Member functions

(constructor): Construct bernoulli distribution (public member function)

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

reset: Reset distribution (public member function)

param: Distribution parameters (public member function)

min: Minimum value (public member function)

max: Maximum value (public member function)

Distribution parameters:

p: Probability of true (public member function)

Non-member functions

operator<<: Insert into output stream (function template)

operator>>: Extract from input stream (function template)

relational operators: Relational operators (function template)

Example

// bernoulli_distribution
#include <iostream>
#include <random>

int main()
{
  const int nrolls=10000;

  std::default_random_engine generator;
  std::bernoulli_distribution distribution(0.5);

  int count=0;  // count number of trues

  for (int i=0; i<nrolls; ++i) if (distribution(generator)) ++count;

  std::cout << "bernoulli_distribution (0.5) x 10000:" << std::endl;
  std::cout << "true:  " << count << std::endl;
  std::cout << "false: " << nrolls-count << std::endl;

  return 0;
}

Possible output:

bernoulli_distribution (0.5) x 10000:
true:  4994
false: 5006