QueueArray

public class QueueArray {
    public static void main(String[] args){
        Queue mqu = new Queue(6);
        mqu.in(65);
        mqu.in(83);
        mqu.in(29);
        mqu.in(25);
        System.out.println(mqu.amount());
        System.out.println(mqu.out());
        System.out.println(mqu.amount());
    }
}

class Queue{
    private Object[] arr;
    private int i = 0;
    public Queue(){
        arr = new Object[10];
    }
    public Queue(int a){
        arr = new Object[a];
    }

    //入列
    public void in(Object s){
        if(i<arr.length) {
            arr[i++] = s;
        }else{
            System.out.println("队列已满！");
        }
    }

    //出列
    public Object out(){
      Object temp = arr[0];
      for(int j=0;j<i;j++){
          arr[j]=arr[j+1];
      }
      i--;
      return temp;
    }

    // 队列中元素的个数
    public int amount(){
        return i;
    }

}