1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <random> 11 12 // template<class Engine, size_t k> 13 // class shuffle_order_engine 14 15 // result_type operator()(); 16 17 #include <random> 18 #include <cassert> 19 20 template <class UIntType, UIntType Min, UIntType Max> 21 class rand1 22 { 23 public: 24 // types 25 typedef UIntType result_type; 26 27 private: 28 result_type x_; 29 30 static_assert(Min < Max, "rand1 invalid parameters"); 31 public: 32 33 #ifdef _LIBCPP_HAS_NO_CONSTEXPR 34 // Workaround for lack of constexpr in C++03 35 static const result_type _Min = Min; 36 static const result_type _Max = Max; 37 #endif 38 39 static _LIBCPP_CONSTEXPR result_type min() {return Min;} 40 static _LIBCPP_CONSTEXPR result_type max() {return Max;} 41 42 explicit rand1(result_type sd = Min) : x_(sd) 43 { 44 if (x_ > Max) 45 x_ = Max; 46 } 47 48 result_type operator()() 49 { 50 result_type r = x_; 51 if (x_ < Max) 52 ++x_; 53 else 54 x_ = Min; 55 return r; 56 } 57 }; 58 59 void 60 test1() 61 { 62 typedef std::knuth_b E; 63 64 E e; 65 assert(e() == 152607844u); 66 } 67 68 void 69 test2() 70 { 71 typedef rand1<unsigned long long, 0, 0xFFFFFFFFFFFFFFFFull> E0; 72 typedef std::shuffle_order_engine<E0, 101> E; 73 E e; 74 e.discard(400); 75 assert(e() == 501); 76 } 77 78 void 79 test3() 80 { 81 typedef rand1<unsigned long long, 0, 0xFFFFFFFFFFFFFFFFull> E0; 82 typedef std::shuffle_order_engine<E0, 100> E; 83 E e; 84 e.discard(400); 85 assert(e() == 500); 86 } 87 88 int main() 89 { 90 test1(); 91 test2(); 92 test3(); 93 } 94
