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1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___CXX03___RANDOM_BERNOULLI_DISTRIBUTION_H10#define _LIBCPP___CXX03___RANDOM_BERNOULLI_DISTRIBUTION_H11 12#include <__cxx03/__config>13#include <__cxx03/__random/is_valid.h>14#include <__cxx03/__random/uniform_real_distribution.h>15#include <__cxx03/iosfwd>16 17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)18# pragma GCC system_header19#endif20 21_LIBCPP_PUSH_MACROS22#include <__cxx03/__undef_macros>23 24_LIBCPP_BEGIN_NAMESPACE_STD25 26class _LIBCPP_TEMPLATE_VIS bernoulli_distribution {27public:28 // types29 typedef bool result_type;30 31 class _LIBCPP_TEMPLATE_VIS param_type {32 double __p_;33 34 public:35 typedef bernoulli_distribution distribution_type;36 37 _LIBCPP_HIDE_FROM_ABI explicit param_type(double __p = 0.5) : __p_(__p) {}38 39 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }40 41 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {42 return __x.__p_ == __y.__p_;43 }44 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }45 };46 47private:48 param_type __p_;49 50public:51 // constructors and reset functions52 _LIBCPP_HIDE_FROM_ABI explicit bernoulli_distribution(double __p = 0.5) : __p_(param_type(__p)) {}53 _LIBCPP_HIDE_FROM_ABI explicit bernoulli_distribution(const param_type& __p) : __p_(__p) {}54 _LIBCPP_HIDE_FROM_ABI void reset() {}55 56 // generating functions57 template <class _URNG>58 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {59 return (*this)(__g, __p_);60 }61 template <class _URNG>62 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p);63 64 // property functions65 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }66 67 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }68 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }69 70 _LIBCPP_HIDE_FROM_ABI result_type min() const { return false; }71 _LIBCPP_HIDE_FROM_ABI result_type max() const { return true; }72 73 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const bernoulli_distribution& __x, const bernoulli_distribution& __y) {74 return __x.__p_ == __y.__p_;75 }76 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const bernoulli_distribution& __x, const bernoulli_distribution& __y) {77 return !(__x == __y);78 }79};80 81template <class _URNG>82inline bernoulli_distribution::result_type bernoulli_distribution::operator()(_URNG& __g, const param_type& __p) {83 static_assert(__libcpp_random_is_valid_urng<_URNG>::value, "");84 uniform_real_distribution<double> __gen;85 return __gen(__g) < __p.p();86}87 88template <class _CharT, class _Traits>89_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&90operator<<(basic_ostream<_CharT, _Traits>& __os, const bernoulli_distribution& __x) {91 __save_flags<_CharT, _Traits> __lx(__os);92 typedef basic_ostream<_CharT, _Traits> _OStream;93 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);94 _CharT __sp = __os.widen(' ');95 __os.fill(__sp);96 return __os << __x.p();97}98 99template <class _CharT, class _Traits>100_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&101operator>>(basic_istream<_CharT, _Traits>& __is, bernoulli_distribution& __x) {102 typedef bernoulli_distribution _Eng;103 typedef typename _Eng::param_type param_type;104 __save_flags<_CharT, _Traits> __lx(__is);105 typedef basic_istream<_CharT, _Traits> _Istream;106 __is.flags(_Istream::dec | _Istream::skipws);107 double __p;108 __is >> __p;109 if (!__is.fail())110 __x.param(param_type(__p));111 return __is;112}113 114_LIBCPP_END_NAMESPACE_STD115 116_LIBCPP_POP_MACROS117 118#endif // _LIBCPP___CXX03___RANDOM_BERNOULLI_DISTRIBUTION_H119