#include <thread>
#include <iostream>
using namespace std;

volatile int aantal = 0;

void teller() {
    for (int i = 0; i < 100000; ++i) {
        ++aantal;
    }
}

int main(void) {
    thread t1(&teller);
    thread t2(&teller);
    thread t3(&teller);
    t1.join();
    t2.join();
    t3.join();
    cout << "aantal = " << aantal << endl;
    return 0; 
}