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Showing content from https://cplusplus.com/Uniform_int_distribution below:

class template

std::uniform_int_distribution

template <class IntType = int> class uniform_int_distribution;

Uniform discrete distribution

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

This distribution produces random integers in a range [a,b] where each possible value has an equal likelihood of being produced. This is the distribution function that appears on many trivial random processes (like the result of rolling a die).

The distribution parameters, a and b, are set on construction.

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

For a discrete distribution that can have different probabilities for each possible value, see discrete_distribution.

Template parameters

IntType: An integer type. Aliased as member type result_type.
By default, this is int.

Member types The following aliases are member types of uniform_int_distribution:

member type definition notes result_type The first template parameter (IntType) The type of the numbers generated (defaults to int) param_type not specified The type returned by member param.

Member functions

(constructor): Construct uniform discrete 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:

a: Lower bound of range (public member function)

b: Upper bound of range (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

// uniform_int_distribution
#include <iostream>
#include <random>

int main()
{
  const int nrolls = 10000; // number of experiments
  const int nstars = 95;    // maximum number of stars to distribute

  std::default_random_engine generator;
  std::uniform_int_distribution<int> distribution(0,9);

  int p[10]={};

  for (int i=0; i<nrolls; ++i) {
    int number = distribution(generator);
    ++p[number];
  }

  std::cout << "uniform_int_distribution (0,9):" << std::endl;
  for (int i=0; i<10; ++i)
    std::cout << i << ": " << std::string(p[i]*nstars/nrolls,'*') << std::endl;

  return 0;
}

Possible output:

uniform_int_distribution (0,9):
0: *********
1: *********
2: *********
3: *********
4: *********
5: *********
6: *********
7: *********
8: *********
9: *********