cxx/test/numerics/rand/rand.adapt/rand.adapt.ibits/eval.pass.cpp
2012-04-02 21:00:45 +00:00

142 lines
2.5 KiB
C++

//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <random>
// template<class Engine, size_t w, class UIntType>
// class independent_bits_engine
// result_type operator()();
#include <random>
#include <cassert>
template <class UIntType, UIntType Min, UIntType Max>
class rand1
{
public:
// types
typedef UIntType result_type;
private:
result_type x_;
static_assert(Min < Max, "rand1 invalid parameters");
public:
#ifdef _LIBCPP_HAS_NO_CONSTEXPR
// Workaround for lack of constexpr in C++03
static const result_type _Min = Min;
static const result_type _Max = Max;
#endif
static _LIBCPP_CONSTEXPR result_type min() {return Min;}
static _LIBCPP_CONSTEXPR result_type max() {return Max;}
explicit rand1(result_type sd = Min) : x_(sd)
{
if (x_ > Max)
x_ = Max;
}
result_type operator()()
{
result_type r = x_;
if (x_ < Max)
++x_;
else
x_ = Min;
return r;
}
};
void
test1()
{
typedef std::independent_bits_engine<rand1<unsigned, 0, 10>, 16, unsigned> E;
E e;
assert(e() == 6958);
}
void
test2()
{
typedef std::independent_bits_engine<rand1<unsigned, 0, 100>, 16, unsigned> E;
E e;
assert(e() == 66);
}
void
test3()
{
typedef std::independent_bits_engine<rand1<unsigned, 0, 0xFFFFFFFF>, 32, unsigned> E;
E e(5);
assert(e() == 5);
}
void
test4()
{
typedef std::independent_bits_engine<rand1<unsigned, 0, 0xFFFFFFFF>, 7, unsigned> E;
E e(129);
assert(e() == 1);
}
void
test5()
{
typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 1, unsigned> E;
E e(6);
assert(e() == 1);
}
void
test6()
{
typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 11, unsigned> E;
E e(6);
assert(e() == 1365);
}
void
test7()
{
typedef std::independent_bits_engine<rand1<unsigned, 2, 3>, 32, unsigned> E;
E e(6);
assert(e() == 2863311530u);
}
void
test8()
{
typedef std::independent_bits_engine<std::mt19937, 64, unsigned long long> E;
E e(6);
assert(e() == 16470362623952407241ull);
}
int main()
{
test1();
test2();
test3();
test4();
test5();
test6();
test7();
test8();
}