#include <iostream>
#include <thread>
#include <mutex>
 
static const int num_threads = 10;
 
std::mutex mtx; 
 
//This function will be called from a thread
 
void call_from_thread(int tid) {
	std::lock_guard<std::mutex> lock(mtx);
    std::cout << "Launched by thread " << tid << std::endl;
}
 
int main() {
    std::thread t[num_threads];
 
    //Launch a group of threads
    for (int i = 0; i < num_threads; ++i) {
        t[i] = std::thread(call_from_thread, i);
    }
 
    std::cout << "Launched from the main\n";
 
    //Join the threads with the main thread
    for (int i = 0; i < num_threads; ++i) {
        t[i].join();
    }
 
    return 0;
}

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