Omp single hanging inside for

Quick question ... I have the following code:

void testingOMP()
{
    #pragma omp parallel for
    for(int i=0;i<5;i++)
    {
        #pragma omp single 
        cout << "During single: " <<omp_get_thread_num() << endl;
        cout << "After single: " << omp_get_thread_num() << endl;
    }
}

which hangs, yielding the following result:

During single: 1 After single: 1 After single: after single: 2During single: 0

1

I needed ctrl + c to stop it. The sharing directive ensures that only one thread executes a block of code that has a synchronization barrier at the end. I think the problem is that if I use master (which does not wait) or adds nowait, the program does not crash.

If anyone could tell me why this is happening, they really appreciate me.