Infinite loop in pso cluster algorithm

Question

I am having some trouble with clusters. I am doing some self learning for my course and I wanted to try out a clustering algorithm. This is not my homework.

When I execute this code, which seems perfectly logical, the value &p[] always returns 0 and hence the loop becomes infinite.

for (int i = 0; i < nc; i++)//nc stands for number of clusters
{
    int flag = 1;
    Particle * temp;
    while (flag != 0)
    {
        temp = &p[rand() % n];
        for (int j = 0; j < i; j++)
            if (cluster[i].c.find(temp) != cluster[i].c.end())// 
            {
                flag = 0;
                break;
            }
    }

//copy temp to cluster }

Can somebody tell me what mistake I have made? Or if you have any other suggestions, you can post it here. I would really like to have some new perspective other than mine.

EDIT: As there was no other reasonable answers, I tried rewriting the program, and it was resolved.