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;}