insertAtRank向量算法

Question

我正在嘗試編寫一個程序供大學插入元素到基於向量的數組中。但是，我的insertAtRank和removeAtRank方法似乎不起作用。任何幫助是極大的讚賞。

這是到目前爲止我的代碼：

public class ArrayVector implements Vector { 

    int n ; 
    Object[] A ; 
    Object element ; 

    public ArrayVector() { 
     A = new Object[10] ; 
     n = 0 ; 
    } 

    public int size() { 
     return n; 
    } 

    public boolean isEmpty() { 
     return n == 0; 
    } 

    public Object elemAtRank(int rank) throws RankOutOfBoundsException { 
     return A[rank]; 
    } 

    public Object replaceAtRank(int rank, Object element) throws RankOutOfBoundsException { 
     A[rank] = element ; 
     return element; 
    } 

    public String toString() { 
     int size = size(); 
     String output = "" + size + "\t"; 

     for (int i = 0 ; i < size ; i++){ 
      output += A[i] + " "; 
     } 
     return output; 
    } 

    public void insertAtRank(int rank, Object element) throws RankOutOfBoundsException { 
     for (int i = n ; i < rank ; n--){ 
      A[i] = A[i+1] ; 
     } 
     A[rank] = element ; 
     n++ ; 
    } 

    public Object removeAtRank(int rank) throws RankOutOfBoundsException { 
     element = A[rank]; 
     for (int i = rank ; i < n-2 ; rank++){ 
      A[i] = A[i+1] ; 
     } 
     n = n-1 ; 
     return element ; 
    } 

    public static void main(String[] args) throws RankOutOfBoundsException { 
     ArrayVector newArray = new ArrayVector() ; 

     System.out.println (newArray.toString()) ; 
     newArray.insertAtRank(0, "c"); 
     System.out.println (newArray.toString()) ; 
     newArray.insertAtRank(1, "a"); 
     System.out.println (newArray.toString()) ; 
     newArray.removeAtRank(0) ; 
     System.out.println (newArray.toString()) ; 
     newArray.insertAtRank(2, "t"); 
     System.out.println (newArray.toString()) ; 
    } 
}