Problem: During the research on properties of the greatest common divisor (GCD) of a set of numbers, Ildar, a famous mathematician, introduced a brand new concept of the weakened common divisor (WCD) of a list of pairs of integers.

For a given list of pairs of integers (a_1, b_1), (a_2, b_2), ..., (a_n, b_n) their WCD is arbitrary integer greater than 1, such that it divides at least one element in each pair. WCD may not exist for some lists.

For example, if the list looks like [(12, 15), (25, 18), (10, 24)], then their WCD can be equal to 2, 3, 5 or 6 (each of these numbers is strictly greater than 1 and divides at least one number in each pair).

You're currently pursuing your PhD degree under Ildar's mentorship, and that's why this problem was delegated to you. Your task is to calculate WCD efficiently.

Input

The first line contains a single integer n (1 ≤ n ≤ 150 000) — the number of pairs.

Each of the next n lines contains two integer values a_i, b_i (2 ≤ a_i, b_i ≤ 2 ⋅ 10^9).

Output

Print a single integer — the WCD of the set of pairs. 

If there are multiple possible answers, output any; if there is no answer, print -1.

Examples

Input

3
17 18
15 24
12 15


Output

6

Input

2
10 16
7 17


Output

-1


Input

5
90 108
45 105
75 40
165 175
33 30


Output

5

Note

In the first example the answer is 6 since it divides 18 from the first pair, 24 from the second and 12 from the third ones. Note that other valid answers will also be accepted.

In the second example there are no integers greater than 1 satisfying the conditions.

In the third example one of the possible answers is 5. Note that, for example, 15 is also allowed, but it's not necessary to maximize the output.

Solution (in JAVA):

Solution:
import java.util.*;
import java.util.stream.*;

public class B {

	int MAX = 100000;

	public Object solve() {
		int N = sc.nextInt();
		long [][] Z = sc.nextLongs(N);

		for (int i : rep(2))
			next: for (long p : distinctPrimeDivisors(Z[0][i]))
				if (p >= MAX) {
					for (int j : rep(N)) {
						boolean ok = false;
						for (int k : rep(2))
							ok = ok || (Z[j][k] % p == 0);
						if (!ok)
							continue next;
					}
					exit(p);
				}

		long X = 0;
		for (int i : rep(N))
			X = gcd(X, Z[i][0] * Z[i][1]);

		if (X == 1)
			exit(-1);

		for (int p : rep(2, MAX))
			if (X % p == 0)
				exit(p);

		return null;
	}

	private static final boolean ONE_TEST_CASE = true;

	private static void init() {
	}

	private static long [] distinctPrimeDivisors (long N) {
		List<Long> res = new ArrayList<Long>();
		for (long p = 2; p*p <= N; ++p) {
			if (N % p == 0)
				res.add(p);
			while (N % p == 0)
				N /= p;
		}
		if (N > 1)
			res.add(N);
		return pri(res.toArray(new Long [0]));
	}
	private static long gcd (long x, long y) {
		x *= Long.signum(x); y *= Long.signum(y);
		while (y > 0) { long z = y; y = x%y; x = z; }
		return x;
	}
	private static long [] pri (Long [] A) { return pri(A, new long [A.length]); }
	private static long [] pri (Long [] A, long [] a) { for (int i = 0; i < A.length; ++i) a[i] = A[i]; return a; }
	private static IntStream range(int N) { return IntStream.range(0, N); }
	private static Iterable<Integer> rep (int N) { return rep(0, N); }
	private static Iterable<Integer> rep (final int S, final int T) { return new Iterable<Integer>() { public Iterator<Integer> iterator() { return S < T ? java.util.stream.IntStream.range(S,  T).iterator() : Collections.emptyIterator(); } }; }
	////////////////////////////////////////////////////////////////////////////////////
	private static IOUtils.MyScanner sc = new IOUtils.MyScanner();
	private static Object print (Object o, Object ... A) { IOUtils.print(o, A); return null; }
	private static Object exit (Object o, Object ... A) { print(o, A); IOUtils.exit(); return null; }
	private static class IOUtils {
		public static class MyScanner {
			public String next() { newLine(); return line[index++]; }
			public int nextInt() { return Integer.parseInt(next()); }
			public String nextLine() { line = null; return readLine(); }
			public String [] nextStrings() { return split(nextLine()); }
			public long[] nextLongs() { return nextStream().mapToLong(Long::parseLong).toArray(); }
			public long[][] nextLongs(int N) { return range(N).mapToObj(i -> nextLongs()).toArray(long[][]::new); }
			//////////////////////////////////////////////
			private boolean eol() { return index == line.length; }
			private String readLine() {
				try {
					return r.readLine();
				} catch (Exception e) {
					throw new Error (e);
				}
			}
			private final java.io.BufferedReader r;
			private MyScanner () { this(new java.io.BufferedReader(new java.io.InputStreamReader(System.in))); }
			private MyScanner (java.io.BufferedReader r) {
				try {
					this.r = r;
					while (!r.ready())
						Thread.sleep(1);
					start();
				} catch (Exception e) {
					throw new Error(e);
				}
			}
			private String [] line;
			private int index;
			private void newLine() {
				if (line == null || eol()) {
					line = split(readLine());
					index = 0;
				}
			}
			private java.util.stream.Stream<String> nextStream() { return java.util.Arrays.stream(nextStrings()); }
			private String [] split(String s) { return s.length() > 0 ? s.split(" ") : new String [0]; }
		}
		private static String build(Object o, Object ... A) { return buildDelim(" ", o, A); }
		private static String buildDelim(String delim, Object o, Object ... A) {
			StringBuilder b = new StringBuilder();
			append(b, o, delim);
			for (Object p : A)
				append(b, p, delim);
			return b.substring(delim.length());
		}
		//////////////////////////////////////////////////////////////////////////////////
		private static final java.text.DecimalFormat formatter = new java.text.DecimalFormat("#.#########");
		private static void start() { if (t == 0) t = millis(); }
		private static void append(java.util.function.Consumer<Object> f, java.util.function.Consumer<Object> g, final Object o) {
			if (o.getClass().isArray()) {
				int len = java.lang.reflect.Array.getLength(o);
				for (int i = 0; i < len; ++i)
					f.accept(java.lang.reflect.Array.get(o, i));
			}
			else if (o instanceof Iterable<?>)
				((Iterable<?>)o).forEach(f::accept);
			else
				g.accept(o instanceof Double ? formatter.format(o) : o);
		}
		private static void append(final StringBuilder b, Object o, final String delim) {
			append(x -> { append(b, x, delim); }, x -> b.append(delim).append(x), o);
		}
		private static java.io.PrintWriter pw = new java.io.PrintWriter(System.out);
		private static Object print(Object o, Object ... A) { pw.println(build(o, A)); return null; }
		private static void err(Object o, Object ... A) { System.err.println(build(o, A)); }
		private static boolean PRINT;
		private static void write(Object o) {
			err(o, '(', time(), ')');
			if (PRINT)
				pw.println(o);
		}
		private static void exit() {
			IOUtils.pw.close();
			System.out.flush();
			err("------------------");
			err(time());
			System.exit(0);
		}
		private static long t;
		private static long millis() { return System.currentTimeMillis(); }
		private static String time() { return "Time: " + (millis() - t) / 1000.0; }
		private static void run(int N) {
			try { PRINT = System.getProperties().containsKey("PRINT"); }
			catch (Throwable t) {}

			for (int n = 1; n <= N; ++n) {
				Object res = new B().solve();
				if (res != null)
					write("Case #" + n + ": " + build(res));
			}
			exit();
		}
	}
	public static void main(String[] args) {
		init();
		int N = ONE_TEST_CASE ? 1 : sc.nextInt();
		IOUtils.run(N);
	}
}