View Code of Problem 3929

//异或是位运算 

#include<iostream>
using namespace std;
#include<algorithm>
int main()
{
	int t,n;
	cin>>t;
	while(t--)
	{
		cin>>n;
		int array[n];
		for(int i=0;i<n;i++)
		{
			cin>>array[i];
		}
		sort(array,array+n);
		int rel=0;
		for(int i=0;i<n;i++)
		{
			rel^=array[i];
		}
		cout<<rel<<endl;
	}
}