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authorAnton Samokhvalov <pg83@yandex.ru>2022-02-10 16:45:15 +0300
committerDaniil Cherednik <dcherednik@yandex-team.ru>2022-02-10 16:45:15 +0300
commit72cb13b4aff9bc9cf22e49251bc8fd143f82538f (patch)
treeda2c34829458c7d4e74bdfbdf85dff449e9e7fb8 /util/random/lcg_engine.h
parent778e51ba091dc39e7b7fcab2b9cf4dbedfb6f2b5 (diff)
downloadydb-72cb13b4aff9bc9cf22e49251bc8fd143f82538f.tar.gz
Restoring authorship annotation for Anton Samokhvalov <pg83@yandex.ru>. Commit 1 of 2.
Diffstat (limited to 'util/random/lcg_engine.h')
-rw-r--r--util/random/lcg_engine.h82
1 files changed, 41 insertions, 41 deletions
diff --git a/util/random/lcg_engine.h b/util/random/lcg_engine.h
index 08cc93c845..fcf8ab7166 100644
--- a/util/random/lcg_engine.h
+++ b/util/random/lcg_engine.h
@@ -1,66 +1,66 @@
-#pragma once
-
+#pragma once
+
#include <utility>
-#include <util/generic/typetraits.h>
-
-// common engine for lcg-based RNG's
-// http://en.wikipedia.org/wiki/Linear_congruential_generator
-
+#include <util/generic/typetraits.h>
+
+// common engine for lcg-based RNG's
+// http://en.wikipedia.org/wiki/Linear_congruential_generator
+
namespace NPrivate {
template <typename T>
T LcgAdvance(T seed, T lcgBase, T lcgAddend, T delta) noexcept;
};
-template <typename T, T A, T C>
-struct TFastLcgIterator {
- static_assert(C % 2 == 1, "C must be odd");
-
+template <typename T, T A, T C>
+struct TFastLcgIterator {
+ static_assert(C % 2 == 1, "C must be odd");
+
static constexpr T Iterate(T x) noexcept {
- return x * A + C;
- }
+ return x * A + C;
+ }
static inline T IterateMultiple(T x, T delta) noexcept {
return ::NPrivate::LcgAdvance(x, A, C, delta);
}
-};
-
-template <typename T, T A>
-struct TLcgIterator {
+};
+
+template <typename T, T A>
+struct TLcgIterator {
inline TLcgIterator(T seq) noexcept
- : C((seq << 1u) | (T)1) // C must be odd
- {
- }
-
+ : C((seq << 1u) | (T)1) // C must be odd
+ {
+ }
+
inline T Iterate(T x) noexcept {
- return x * A + C;
- }
-
+ return x * A + C;
+ }
+
inline T IterateMultiple(T x, T delta) noexcept {
return ::NPrivate::LcgAdvance(x, A, C, delta);
}
- const T C;
-};
-
-template <class TIterator, class TMixer>
-struct TLcgRngBase: public TIterator, public TMixer {
+ const T C;
+};
+
+template <class TIterator, class TMixer>
+struct TLcgRngBase: public TIterator, public TMixer {
using TStateType = decltype(std::declval<TIterator>().Iterate(0));
using TResultType = decltype(std::declval<TMixer>().Mix(TStateType()));
-
- template <typename... Args>
- inline TLcgRngBase(TStateType seed, Args&&... args)
+
+ template <typename... Args>
+ inline TLcgRngBase(TStateType seed, Args&&... args)
: TIterator(std::forward<Args>(args)...)
- , X(seed)
- {
- }
-
+ , X(seed)
+ {
+ }
+
inline TResultType GenRand() noexcept {
- return this->Mix(X = this->Iterate(X));
- }
-
+ return this->Mix(X = this->Iterate(X));
+ }
+
inline void Advance(TStateType delta) noexcept {
X = this->IterateMultiple(X, delta);
}
- TStateType X;
-};
+ TStateType X;
+};