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.
#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000000 + 7;
const long long MOD1 = 998244353;
string itos(long long s) {
  string str = to_string(s);
  return str;
}
long long stoi2(string s) {
  long long a = atoi(s.c_str());
  return a;
}
template <typename T>
void read(T &p) {
  cin >> p;
}
template <typename T, typename T1>
void read(pair<T, T1> &p) {
  read(p.first);
  read(p.second);
}
template <typename T>
void read(T arr[], long long n) {
  for (long long i = 0; i < n; i++) {
    read(arr[i]);
  }
}
template <typename T>
void read(vector<T> &arr) {
  for (long long i = 0; i < arr.size(); i++) {
    read(arr[i]);
  }
}
template <typename T>
void out(T &n) {
  cout << n;
}
template <typename T, typename T1>
void out(pair<T, T1> &p) {
  cout << "(";
  out(p.first);
  cout << ",";
  out(p.second);
  cout << ")";
  cout << endl;
}
template <typename T>
void out(T arr[], long long n) {
  for (long long i = 0; i < n; i++) {
    out(arr[i]);
    cout << " ";
  }
  cout << endl;
}
template <typename T>
void out(vector<T> &arr) {
  for (long long i = 0; i < arr.size(); i++) {
    out(arr[i]);
    if (i != arr.size() - 1) cout << " ";
  }
  cout << endl;
}
template <typename T>
void out(set<T> &arr) {
  for (auto i : arr) {
    out(i);
    cout << " ";
  }
  cout << endl;
}
template <typename T>
void out(multiset<T> &arr) {
  for (auto i : arr) {
    out(i);
    cout << " ";
  }
  cout << endl;
}
template <typename T, typename T1>
void out(map<T, T1> &m) {
  for (auto i : m) {
    out(i.first);
    cout << " -> ";
    out(i.second);
    cout << ", ";
  }
  cout << endl;
}
long long powerm(long long a, long long b, long long MOD) {
  a %= MOD;
  long long res = 1;
  while (b > 0) {
    if (b & 1) res = res * a % MOD;
    a = a * a % MOD;
    b >>= 1;
  }
  return res;
}
long long power(long long a, long long b) {
  long long res = 1;
  while (b > 0) {
    if (b & 1) res = res * a;
    a = a * a;
    b >>= 1;
  }
  return res;
}
bool isSubSequence(string str1, string str2, int m, int n) {
  if (m == 0) return true;
  if (n == 0) return false;
  if (str1[m - 1] == str2[n - 1])
    return isSubSequence(str1, str2, m - 1, n - 1);
  return isSubSequence(str1, str2, m, n - 1);
}
bool ispalindrome(long long len, string str) {
  for (int i = 0; i < len / 2; i++) {
    if (str[i] != str[len - 1 - i]) {
      return false;
    }
  }
  return true;
}
inline bool isPowerOfTwo(long long x) {
  return ((1LL << (long long)log2(x)) == x);
}
long long isprime(long long N) {
  if (N < 2 || (!(N & 1) && N != 2)) return 0;
  for (long long i = 3; i * i <= N; i += 2) {
    if (!(N % i)) return 0;
  }
  return 1;
}
vector<long long> factor;
void factors(long long n) {
  for (long long i = 1; i <= sqrt(n); i++) {
    if (n % i == 0) {
      if (i == n / i)
        factor.push_back(i);
      else {
        factor.push_back(i);
        factor.push_back(n / i);
      }
    }
  }
  sort((factor).begin(), (factor).end());
}
long long gcd(long long a, long long b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
long long lcm(long long a, long long b) { return (a / gcd(a, b)) * b; }
bool isvalid(long long i, long long j, long long n) {
  if (i >= 0 && i < n && j >= 0 && j < n) return true;
  return false;
}
long long dx[8] = {0, 1, 1, 1, 0, -1, -1, -1};
long long dy[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
long long binarytodecimal(string n) {
  string num = n;
  long long dec_value = 0;
  long long base = 1;
  long long len = num.length();
  for (int i = len - 1; i >= 0; i--) {
    if (num[i] == '1') dec_value += base;
    base = base * 2;
  }
  return dec_value;
}
long long extended_GCD(long long a, long long b, long long &x, long long &y) {
  if (a == 0) {
    x = 0;
    y = 1;
    return b;
  }
  long long x1, y1;
  long long gcd = extended_GCD(b % a, a, x1, y1);
  x = y1 - (b / a) * x1;
  y = x1;
  return gcd;
}
long long modinv(long long a, long long mod = MOD) {
  long long x, y;
  extended_GCD(a, mod, x, y);
  if (x < 0) x += mod;
  return x;
}
string dtb(long long n) {
  string s = "";
  while (n > 0) {
    if (n % 2 == 0)
      s.push_back('0');
    else
      s.push_back('1');
    n /= 2;
  }
  reverse((s).begin(), (s).end());
  return s;
}
long long getfactorisation(long long n) {
  long long N = 5e6 + 5;
  vector<long long> fact(N);
  for (int i = 0; i < N; i++) fact[i] = i;
  for (int i = 2; i < N; i += 2) fact[i] = 2;
  for (long long i = 3; i <= N; i += 2)
    if (i == fact[i])
      for (long long j = i * i; j < N; j += i)
        if (fact[j] == j) fact[j] = i;
  vector<long long> res;
  while (n > 1) {
    res.push_back(fact[n]);
    n /= fact[n];
  }
  return res.size();
}
long long maxPrimeFactor(long long n) {
  long long maxPrime = -1;
  while (n % 2 == 0) {
    maxPrime = 2;
    n >>= 1;
  }
  for (int i = 3; i <= sqrt(n); i += 2) {
    while (n % i == 0) {
      maxPrime = i;
      n = n / i;
    }
  }
  if (n > 2) maxPrime = n;
  return maxPrime;
}
vector<long long> seive;
void Seive() {
  const long long maxn = 1e6 + 5;
  seive.resize(maxn);
  for (long long i = (long long)0; i < (long long)maxn; i++) seive[i] = i;
  for (long long i = 2; i <= maxn; i += 2) seive[i] = 2;
  seive[1] = -1;
  seive[0] = -1;
  for (long long i = 3; i <= maxn; i += 2)
    if (i == seive[i])
      for (long long j = i * i; j < maxn; j += i)
        if (seive[j] == j) seive[j] = i;
}
void factorisation(long long n) {
  vector<long long> res;
  for (long long i = 2; i * i <= n; i++) {
    if (n % i == 0) {
      while (n % i == 0) {
        n /= i;
        res.push_back(i);
      }
    }
  }
  if (n > 1) res.push_back(n);
}
int numOfDivisors[100005] = {0};
void noOfDivisor() {
  for (int i = 1; i <= 100005; i++)
    for (int j = i; j <= 100005; j += i) {
      numOfDivisors[j]++;
    }
}
long long fac[200005];
unsigned long long modInverse(unsigned long long n, int p) {
  return powerm(n, p - 2, p);
}
long long nCrModPFermat(unsigned long long n, int r, int p) {
  if (n < r) return 0;
  if (r == 0) return 1;
  unsigned long long fac[n + 1];
  fac[0] = 1;
  for (int i = 1; i <= n; i++) fac[i] = (fac[i - 1] * i) % p;
  return (fac[n] * modInverse(fac[r], p) % p * modInverse(fac[n - r], p) % p) %
         p;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  long long T = 1;
  while (T--) {
    long long n;
    cin >> n;
    vector<pair<long long, long long> > v;
    for (long long i = (long long)0; i < (long long)n; i++) {
      long long a, b;
      cin >> a >> b;
      v.push_back({a, b});
    }
    vector<long long> fact;
    for (int i = 2; i * i <= v[0].first; i++) {
      long long c = 0;
      while (v[0].first % i == 0) {
        v[0].first /= i;
        c++;
      }
      if (c) fact.push_back(i);
    }
    for (int i = 2; i * i <= v[0].second; i++) {
      long long c = 0;
      while (v[0].second % i == 0) {
        v[0].second /= i;
        c++;
      }
      if (c) fact.push_back(i);
    }
    fact.push_back(v[0].second);
    fact.push_back(v[0].first);
    for (auto x : fact) {
      long long fk = 1;
      for (long long i = (long long)1; i < (long long)n; i++) {
        if (v[i].first % x == 0 || v[i].second % x == 0) {
        } else {
          fk = 0;
          break;
        }
      }
      if (fk) {
        cout << x;
        exit(0);
      }
    }
    cout << -1;
  }
}
