std* Delete_Stud (std* toDel, std* head)
{

    std *prev=head, *prevHead = temp;

    if(toDel==head)
    {
        free(toDel);
        return NULL;
    }
    if(toDel->next==NULL)
    {
        free(toDel);
        reuturn head;
    }
    while(head!=NULL)
    {
        prev = head;
        head = head->next;
    }
    prev->next = toDel->next;
    free(toDel);
    return prevHead;
}