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/* boost random/random_number_generator.hpp header file
*
* Copyright Jens Maurer 2000-2001
* Distributed under the Boost Software License, Version 1.0. (See
* accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* See http://www.boost.org for most recent version including documentation.
*
* $Id: random_number_generator.hpp 71018 2011-04-05 21:27:52Z steven_watanabe $
*
* Revision history
* 2001-02-18 moved to individual header files
*/
#ifndef BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP
#define BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP
#include <boost/assert.hpp>
#include <boost/random/uniform_int_distribution.hpp>
#include <boost/random/detail/disable_warnings.hpp>
namespace boost {
namespace random {
/**
* Instantiations of class template random_number_generator model a
* RandomNumberGenerator (std:25.2.11 [lib.alg.random.shuffle]). On
* each invocation, it returns a uniformly distributed integer in
* the range [0..n).
*
* The template parameter IntType shall denote some integer-like value type.
*/
template<class URNG, class IntType = long>
class random_number_generator
{
public:
typedef URNG base_type;
typedef IntType argument_type;
typedef IntType result_type;
/**
* Constructs a random_number_generator functor with the given
* \uniform_random_number_generator as the underlying source of
* random numbers.
*/
random_number_generator(base_type& rng) : _rng(rng) {}
// compiler-generated copy ctor is fine
// assignment is disallowed because there is a reference member
/**
* Returns a value in the range [0, n)
*/
result_type operator()(argument_type n)
{
BOOST_ASSERT(n > 0);
return uniform_int_distribution<IntType>(0, n-1)(_rng);
}
private:
base_type& _rng;
};
} // namespace random
using random::random_number_generator;
} // namespace boost
#include <boost/random/detail/enable_warnings.hpp>
#endif // BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP
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