43 lines
1.2 KiB
C++
43 lines
1.2 KiB
C++
// Copyright 2010 Google
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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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#ifndef OR_TOOLS_BASE_RANDOM_H_
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#define OR_TOOLS_BASE_RANDOM_H_
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#include "base/basictypes.h"
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namespace operations_research {
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// ACM minimal standard random number generator. (re-entrant.)
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class ACMRandom {
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public:
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explicit ACMRandom(int32 seed) : seed_(seed) {}
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int32 Next();
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int32 Uniform(int32 max_value);
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int64 Next64();
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float RndFloat() {
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return Next() * 0.000000000465661273646; // x: x * (M-1) = 1 - eps
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}
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void Reset(int32 seed) { seed_ = seed; }
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static int32 HostnamePidTimeSeed();
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static int32 DeterministicSeed();
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private:
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int32 seed_;
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};
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} // namespace operations_research
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#endif // OR_TOOLS_BASE_RANDOM_H_
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