proj/proj1b/ArrayDeque.java
private int addpointerFirst(int nextFirst) {
        if (nextFirst != 0) {
            // move First pointer backward
            nextFirst -= 1;
        } else {
            // move First pointer to the end of Array.
            nextFirst = Array.length - 1;
        }
        return nextFirst;
    }
/**  private helper function.
     *
     *   move First pointer when adding element.
     * */
private helper function.
move First pointer when adding element.
private helper function . move First pointer when adding element .
private int addpointerFirst(int nextFirst) {
        if (nextFirst != 0) {
            nextFirst -= 1;
        } else {
            nextFirst = Array.length - 1;
        }
        return nextFirst;
    }
private int addpointerFirst ( int nextFirst ) { if ( nextFirst != 0 ) { nextFirst -= 1 ; } else { nextFirst = Array . length - 1 ; } return nextFirst ; }
private helper function.
private helper function .
// move First pointer backward // move First pointer to the end of Array.