#include <stdio.h>

const int Mod = 998244353;

void merge_sort(int n, int x[])
{
	static int y[200001] = {};
	if (n <= 1) return;
	merge_sort(n / 2, &(x[0]));
	merge_sort((n + 1) / 2, &(x[n/2]));
	
	int i, p, q;
	for (i = 0, p = 0, q = n / 2; i < n; i++) {
		if (p >= n / 2) y[i] = x[q++];
		else if (q >= n) y[i] = x[p++];
		else y[i] = (x[p] < x[q])? x[p++]: x[q++];
	}
	for (i = 0; i < n; i++) x[i] = y[i];
}

int main()
{
	int i, N, A[200001];
	scanf("%d", &N);
	for (i = 0; i < N; i++) scanf("%d", &(A[i]));
	merge_sort(N, A);
	
	int n = 0, B[200001];
	for (i = 1, B[n++] = A[0]; i < N; i++) if (B[n-1] != A[i]) B[n++] = A[i];
	
	int j, bit[31], flag[31] = {};
	for (i = 1, bit[0] = 1; i <= 30; i++) bit[i] = bit[i-1] << 1;
	for (i = 0; i < n - 1; i++) {
		for (j = 30; j >= 0; j--) if ((B[i] & bit[j]) != (B[i+1] & bit[j])) break;
		flag[j] = 1;
	}
	
	int ans = 1;
	for (i = 0; i <= 30; i++) if (flag[i] != 0) ans <<= 1;
	printf("%d\n", ans);
	fflush(stdout);
	return 0;
}