/
atomic.cc
67 lines (53 loc) · 1.07 KB
/
atomic.cc
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#include <iostream>
#include <thread>
#include <vector>
class A {
private:
// std::atomic<int> value;
std::atomic_int value;
// int value;
public:
A() : value(0) {}
void increase() {
++value;
}
void decrease() {
--value;
}
void print() {
std::cout << value << std::endl;
}
};
class B {
private:
std::mutex mutex;
int value;
public:
B() : value(0) {}
void increase() {
std::lock_guard<std::mutex> lock(mutex);
++value;
}
void decrease() {
--value;
}
void print() {
std::cout << value << std::endl;
}
};
int main() {
A b;
std::vector<std::thread> threads;
for (int i=0; i<100; ++i) {
threads.push_back(std::thread([&b]() {
for (int j=0; j<10000; ++j) {
b.increase();
}
}));
}
for (auto& t: threads) {
t.join();
}
b.print();
return 0;
}