51 lines
1.5 KiB
C++
51 lines
1.5 KiB
C++
/*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Copyright 2016 Danny Robson <danny@nerdcruft.net>
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*/
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#ifndef __UTIL_RANDOM_HPP
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#define __UTIL_RANDOM_HPP
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#include <random>
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///////////////////////////////////////////////////////////////////////////////
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namespace util::rand {
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//-------------------------------------------------------------------------
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using default_generator = std::minstd_rand;
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//-------------------------------------------------------------------------
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template <typename Generator = default_generator>
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Generator&
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thread_engine (void)
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{
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std::random_device rd;
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thread_local Generator gen (rd ());
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return gen;
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}
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//-------------------------------------------------------------------------
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template <typename Generator = default_generator, typename T, size_t N>
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T&
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choose (T (&t)[N], Generator gen = thread_engine<Generator> ())
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{
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std::uniform_int_distribution<size_t> dist (0, N-1);
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return t[dist (gen)];
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}
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}
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#endif
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