#include <iostream>
using namespace std;
int min(int a[], int n) {
	int min = a[0];
	for (int i = 1; i < n; i++) {
		if (a[i] < min) min = a[i];
	}
	return min;
}
int uoclonnhat(int a[], int n) {
	int dem = 0;
	for (int i = min(a, n); i > 0; i--) {
		for (int j = 0; j < n; j++) {
			if (a[j] % i == 0) {
				dem++;
			}
		}
		if (dem == n)
		{
			return i;
		}
		else dem = 0;
	}
}
int main() {
	int n, a[100];
	cout << "Nhap so phan tu co trong mang a: ";
	cin >> n;
	for (int i = 0; i < n; i++) {
		do {
			cout << "Nhap so thu " << i + 1 << " trong mang: ";
			cin >> a[i];
		} while (a[i] <= 0);
	}
	int dem = 0;
	for (int k = uoclonnhat(a, n) - 1; k > 0; k--) {
		for (int j = 0; j < n; j++) {
			if (a[j] % k == 0) {
				dem++;
			}
		}
		if (dem == n) {
			cout << k;
			return 1;
		}
		else dem = 0;
	}
	return 0;
}