计数在OpenMP中无法正常工作

I have the function

我有这个功能

void collatz(int startNumber, int endNumber, int* iter, int nThreads)
{
    int i, n, counter;
    int isodd; /* 1 if n is odd, 0 if even */
    #pragma omp parallel for
    for (i = startNumber; i <= endNumber; i++)
    {
        counter = 0;
        n = i;
        omp_set_num_threads(nThreads);
        while (n > 1)
        {
            isodd = n%2;
            if (isodd)
                n = 3*n+1;
            else
                n/=2;
            counter++;
        }
        iter[i - startNumber] = counter;
    }
}
void collatz(int