27 lines
395 B
C++
27 lines
395 B
C++
//
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// Created by light on 20-2-7.
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//
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#include <iostream>
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using namespace std;
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#include <mutex>
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class singleton {
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private:
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singleton() {}
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static singleton *p;
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static mutex lock_;
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public:
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static singleton *instance();
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};
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singleton *singleton::p = nullptr;
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singleton *singleton::instance() {
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lock_guard<mutex> guard(lock_);
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if (p == nullptr)
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p = new singleton();
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return p;
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}
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