#include<stdio.h>

#include<stdlib.h>

int singleNumber(int* nums, int numsSize)

{

	int count[32]={0};

	int i,j,number=0;

	for(i=0;i<numsSize;i++)

	{

		for(j=0;j<32;j++)

			count[j]+=((nums[i]&(1<<j))!=0);

	}

	for(i=0;i<32;i++)

	{

		if(count[i]%3!=0)

			number+=(1<<i);

	}

	return number;

}

int main()

{

	int n;

	int i,j=0;

	while(scanf("%d",&n)!=EOF)

	{

		int *nums=(int *)malloc(sizeof(int)*n);

		for(i=0;i<n;i++)

			scanf("%d",&nums[i]);

		j=singleNumber(nums, n);

		printf("%d\n",j);

	}

	return 0;

}