请大神帮我

int DeleteDate(int a)
{
    sNode *p=NULL,*q = pHead;
    while (q)
    {   
        if (q->data.iNum == a)
                  p->pNext = q->pNext;
            free(q);
            q= p->pNext;
            continue;
    }
    p = q;
    q = q->pNext;
    return 0;
}