public class MyArray {
   private long[] arr;
   //表示有效数据的长度
   private int elements;
   
   public MyArray() {
      arr = new long[50];
   }
   
   public MyArray(int maxsize) {
      arr = new long[maxsize];
   }
   
   /**
    * 添加数据
    */
   public void insert(long value) {
      arr[elements] = value;
      elements++;
   }
   
   /**
    * 显示数据
    */
   public void display() {
      System.out.print("[");
      for(int i = 0; i < elements; i++) {
         System.out.print(arr[i] + " ");
      }
      System.out.println("]");
   }
   
   /**
    * 查找数据
    */
   public int search(long value) {
      int i;
      for(i = 0; i < elements; i++) {
         if(value == arr[i]) {
            break;
         }
      }
      
      if(i == elements) {
         return -1;
      } else {
         return i;
      }
      
   }
   
   /**
    * 查找数据，根据索引来查
    */
   public long get(int index) {
      if(index >= elements || index < 0) {
         throw new ArrayIndexOutOfBoundsException();
      } else {
         return arr[index];
      }
   }
   
   /**
    * 删除数据
    */
   public void delete(int index) {
      if(index >= elements || index < 0) {
         throw new ArrayIndexOutOfBoundsException();
      } else {
         for(int i = index; i < elements; i++) {
            arr[index] = arr[index + 1];
         }
         elements--;
      }
   }
   
   /**
    * 更新数据
    */
   public void change(int index, int newvalue) {
      if(index >= elements || index < 0) {
         throw new ArrayIndexOutOfBoundsException();
      } else {
         arr[index] = newvalue;
      }
   }
}