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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___RANDOM_GEOMETRIC_DISTRIBUTION_H10#define _LIBCPP___RANDOM_GEOMETRIC_DISTRIBUTION_H11 12#include <__config>13#include <__random/is_valid.h>14#include <__random/negative_binomial_distribution.h>15#include <iosfwd>16#include <limits>17 18#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)19# pragma GCC system_header20#endif21 22_LIBCPP_PUSH_MACROS23#include <__undef_macros>24 25_LIBCPP_BEGIN_NAMESPACE_STD26 27template <class _IntType = int>28class geometric_distribution {29 static_assert(__libcpp_random_is_valid_inttype<_IntType>::value, "IntType must be a supported integer type");30 31public:32 // types33 typedef _IntType result_type;34 35 class param_type {36 double __p_;37 38 public:39 typedef geometric_distribution distribution_type;40 41 _LIBCPP_HIDE_FROM_ABI explicit param_type(double __p = 0.5) : __p_(__p) {}42 43 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_; }44 45 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const param_type& __x, const param_type& __y) {46 return __x.__p_ == __y.__p_;47 }48 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const param_type& __x, const param_type& __y) { return !(__x == __y); }49 };50 51private:52 param_type __p_;53 54public:55 // constructors and reset functions56#ifndef _LIBCPP_CXX03_LANG57 _LIBCPP_HIDE_FROM_ABI geometric_distribution() : geometric_distribution(0.5) {}58 _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(double __p) : __p_(__p) {}59#else60 _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(double __p = 0.5) : __p_(__p) {}61#endif62 _LIBCPP_HIDE_FROM_ABI explicit geometric_distribution(const param_type& __p) : __p_(__p) {}63 _LIBCPP_HIDE_FROM_ABI void reset() {}64 65 // generating functions66 template <class _URNG>67 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g) {68 return (*this)(__g, __p_);69 }70 template <class _URNG>71 _LIBCPP_HIDE_FROM_ABI result_type operator()(_URNG& __g, const param_type& __p) {72 return negative_binomial_distribution<result_type>(1, __p.p())(__g);73 }74 75 // property functions76 _LIBCPP_HIDE_FROM_ABI double p() const { return __p_.p(); }77 78 _LIBCPP_HIDE_FROM_ABI param_type param() const { return __p_; }79 _LIBCPP_HIDE_FROM_ABI void param(const param_type& __p) { __p_ = __p; }80 81 _LIBCPP_HIDE_FROM_ABI result_type min() const { return 0; }82 _LIBCPP_HIDE_FROM_ABI result_type max() const { return numeric_limits<result_type>::max(); }83 84 friend _LIBCPP_HIDE_FROM_ABI bool operator==(const geometric_distribution& __x, const geometric_distribution& __y) {85 return __x.__p_ == __y.__p_;86 }87 friend _LIBCPP_HIDE_FROM_ABI bool operator!=(const geometric_distribution& __x, const geometric_distribution& __y) {88 return !(__x == __y);89 }90};91 92template <class _CharT, class _Traits, class _IntType>93_LIBCPP_HIDE_FROM_ABI basic_ostream<_CharT, _Traits>&94operator<<(basic_ostream<_CharT, _Traits>& __os, const geometric_distribution<_IntType>& __x) {95 __save_flags<_CharT, _Traits> __lx(__os);96 typedef basic_ostream<_CharT, _Traits> _OStream;97 __os.flags(_OStream::dec | _OStream::left | _OStream::fixed | _OStream::scientific);98 return __os << __x.p();99}100 101template <class _CharT, class _Traits, class _IntType>102_LIBCPP_HIDE_FROM_ABI basic_istream<_CharT, _Traits>&103operator>>(basic_istream<_CharT, _Traits>& __is, geometric_distribution<_IntType>& __x) {104 typedef geometric_distribution<_IntType> _Eng;105 typedef typename _Eng::param_type param_type;106 __save_flags<_CharT, _Traits> __lx(__is);107 typedef basic_istream<_CharT, _Traits> _Istream;108 __is.flags(_Istream::dec | _Istream::skipws);109 double __p;110 __is >> __p;111 if (!__is.fail())112 __x.param(param_type(__p));113 return __is;114}115 116_LIBCPP_END_NAMESPACE_STD117 118_LIBCPP_POP_MACROS119 120#endif // _LIBCPP___RANDOM_GEOMETRIC_DISTRIBUTION_H121