import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		//		new Main().solveA();
		//		new Main().solveB();
		new Main().solveC();
		// new Main().solveD();
	}

	private void solveA() {
		Scanner scanner = null;
		int lineAB = 0;
		int lineBC = 0;

		try {
			scanner = new Scanner(System.in);
			lineAB = scanner.nextInt();
			lineBC = scanner.nextInt();

			if (lineBC % lineAB == 0) {
				System.out.println(lineAB + lineBC);
			} else {
				System.out.println(lineBC - lineAB);
			}

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private void solveB() {
		Scanner scanner = null;
		int nNin = 0;
		int mSyurui = 0;

		try {
			scanner = new Scanner(System.in);
			String line1 = scanner.nextLine();
			String[] wkStr1 = line1.split(" ");
			nNin = Integer.parseInt(wkStr1[0]);
			mSyurui = Integer.parseInt(wkStr1[1]);

			List<List<Integer>> wkList = new ArrayList<List<Integer>>();

			for (int i = 0; i < nNin; i++) {
				String wk = scanner.nextLine();
				String[] wkStr = wk.split(" ");
				List<Integer> wkInnerList = new ArrayList<Integer>();
				for (int j = 1; j < wkStr.length; j++) {
					wkInnerList.add(Integer.parseInt(wkStr[j]));
				}
				wkList.add(wkInnerList);
			}

			int result = 0;
			List<Integer> alreadyFinishList = new ArrayList<Integer>();
			for (int i = 0; i < wkList.size(); i++) {
				List<Integer> wkInnerList = wkList.get(i);
				for (int i2 = 0; i2 < wkInnerList.size(); i2++) {
					int syokuNum = wkInnerList.get(i2);
					if (alreadyFinishList.contains(syokuNum)) {
						continue;
					}
					if (isContain(nNin, wkList, i, syokuNum)) {
						result++;
					}
					alreadyFinishList.add(syokuNum);
				}

			}
			System.out.println(result);

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private boolean isContain(int nNin, List<List<Integer>> wkList, int i, int syokuNum) {
		int result = 0;
		for (int j = 0; j < nNin; j++) {
			if (i == j || j >= wkList.size()) {
				continue;
			}

			List<Integer> wkSarchList = wkList.get(j);
			if (wkSarchList.contains(syokuNum)) {
				result++;
			}

		}
		return result == nNin - 1;
	}

	public long maximuKouyakuNArgs(long currentKouyaku, long[] nums, int start) {
		long res = currentKouyaku;
		if (start < nums.length && start != nums.length) {
			res = maximumKouyaku2Args(nums[start], currentKouyaku);
			return maximuKouyakuNArgs(res, nums, start + 1);
		} else {
			return res;
		}
	}

	public long maximumKouyaku2Args(long num1, long num2) {
		try {
			long wkVal1;
			long wkVal2;
			if (num1 < num2) {
				wkVal1 = num2;
				wkVal2 = num1;
			} else {
				wkVal1 = num1;
				wkVal2 = num2;
			}
			long res = wkVal1 % wkVal2;
			if (res != 0) {
				return maximumKouyaku2Args(wkVal2, res);
			} else {
				return wkVal2;
			}

		} catch (Exception e) {
			System.out.println("num1 : " + num1 + " / num2:" + num2);
			e.printStackTrace();
			return -1;
		}

	}

	private void solveC() {
		Scanner scanner = null;
		int monsterNum = 0;

		try {
			scanner = new Scanner(System.in);
			monsterNum = scanner.nextInt();
			long[] monsters = new long[monsterNum];
			for (int i = 0; i < monsterNum; i++) {
				monsters[i] = scanner.nextInt();
			}
			//
			//			Arrays.sort(monsters);
			//			int minHP = Integer.MAX_VALUE;
			//			if (monsters[0] == monsters[monsters.length - 1]) {
			//				System.out.println(monsters[0]);
			//				return;
			//			} else {
			//				minHP = getMinHP(monsters, minHP);
			//			}
			System.out.println(maximuKouyakuNArgs(monsters[0], monsters, 0));

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}

	private Map<Integer, Integer> wkHP = new HashMap<Integer, Integer>();

	private int getMinHP(int[] monsters, int minHP) {
		int resultHP = minHP;
		try {
			if (wkHP.get(minHP) != null) {
				return wkHP.get(minHP);
			}
			for (int i = 0; i < monsters.length; i++) {
				if (i == 0) {
					continue;
				}
				if (monsters[i] % monsters[0] == 0) {
					resultHP = Math.min(monsters[0], resultHP);
				} else {
					resultHP = Math.min(monsters[i] % monsters[0], resultHP);
				}
			}
			if (resultHP > 2) {
				resultHP = getMinHP(monsters, resultHP);
			}
			wkHP.put(minHP, resultHP);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return resultHP;

	}

	private void solveD() {
		Scanner scanner = null;
		int lineAB = 0;
		int lineBC = 0;
		int lineCA = 0;

		try {
			scanner = new Scanner(System.in);
			lineAB = scanner.nextInt();

			System.out.println("");

		} finally {
			if (scanner != null) {
				scanner.close();
			}
		}
	}
}

Measured memory_bytes: 72980