#include <bits/stdc++.h>
using namespace std;
const long long maxN = 1e6 + 5;
const long long inf = 1e10;
const long long mod = 1e9 + 7;
long long n;
long long x[maxN];
long long a, b;
int main() {
  ios_base::sync_with_stdio(0);
  cin >> n;
  for (long long i = 1; i <= n; i++) cin >> x[i];
  cin >> a >> b;
  sort(x + 1, x + 1 + n);
  n = unique(x + 1, x + 1 + n) - (x + 1);
  long long res = 0;
  while (a > b) {
    long long next = a - 1;
    for (long long i = 1; i <= n; i++) {
      long long tmp = a - a % x[i];
      if (tmp < b) {
        x[i--] = x[--n];
      } else if (tmp < next)
        next = tmp;
    }
    a = next;
    res++;
  }
  cout << res;
  return 0;
}
