方法一

    
    
    public static void swap(int[] arr,int i,int j){
        arr[i]=arr[i]^arr[j];
        arr[j]=arr[i]^arr[j];
        arr[i]=arr[i]^arr[j];
        
    }
方法二
    public static void swap(int[] arr,int i,int j){
        int temp=arr[i];
        arr[i]=arr[j];
        arr[j]=temp;
    }