Code 404

void unify(int p, int q) {
            int root1 = find(p);
            int root2 = find(q);

            if (root1 == root2)
                return;
            if (sz[root1] < sz[root2]) {
                sz[root2] += sz[root1];
                id[root1] = root2;
            } else {
                sz[root1] += sz[root2];
                id[root2] = root1;
            }

            numComponents--;
        }

  int find(int p) {
            int root = p;

            while (root != id[root])
                root = id[root];

            while (p != root) {
                int next = id[p];
                id[p] = root;
                p = next;
            }

            return root;
        }