std::binomial_distribution<IntType>:: binomial_distribution

From cppreference.com
binomial_distribution ( ) : binomial_distribution ( 1 ) { }
(1) (since C++11)
explicit binomial_distribution ( IntType t, double p = 0.5 ) ;
(2) (since C++11)
explicit binomial_distribution ( const param_type & params ) ;
(3) (since C++11)

Constructs a new distribution object.

2) Uses t and p as the distribution parameters.
3) Uses params as the distribution parameter.

Parameters

t - the t distribution parameter (number of trials)
p - the p distribution parameter (probability of a trial generating true )
params - the distribution parameter set

Notes

Requires that 0 ≤ p ≤ 1 and 0 ≤ t .

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
P0935R0 C++11 default constructor was explicit made implicit