mutexSemaforo

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


mutex semaforo;

void imprime(int n, char c)
{
    semaforo.lock();
    for(int i = 0; i < n; i++)
    {
        cout << c ;
    }cout << endl;
    semaforo.unlock();
}

int main()
{
   thread t1(imprime, 50, 'a');
    thread t2(imprime, 50, 'b');
     thread t3(imprime, 50, 'c');
      thread t4(imprime, 50, 'd');

      t1.join();
      t2.join();
      t3.join();
      t4.join();

    return 0;
}