#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define T     \
  ll rrr;     \
  cin >> rrr; \
  for (ll w1 = 0; w1 < rrr; w1++)
#define cin(vec, a) for (ll i = 0; i < a && cin >> vec[i]; i++)
#define cout(vec, a) for (ll i = 0; i < a && cout << vec[i] << " "; i++)
#define MOD 1000000007
#define PI 3.14159265
#define ceil(a, b) ((a / b) + (a % b ? 1 : 0))
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#include <iostream>
#define INF 1e9
#define mod 1000000007
#include <string>
#define el '\n'
#define sp ' '
#define loop(n) for (int i = 0; i < n; i++)
typedef long long ll;
#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define multi_ordered_set tree<ll, null_type, greater_equal<ll>, rb_tree_tag, tree_order_statistics_node_update>
template <typename O = int>
istream &operator>>(istream &in, vector<O> &v)
{
  for (auto &x : v)
    in >> x;
  return in;
}
template <typename O = int>
ostream &operator<<(ostream &out, const vector<O> &v)
{
  for (const O &x : v)
    out << x << ' ';
  return out;
}
void sasa()
{
  ios_base::sync_with_stdio(false), cin.tie(nullptr), cout.tie(nullptr);
#ifndef ONLINE_JUDGE
  freopen("input4.txt", "r", stdin), freopen("output4.txt", "w", stdout);
#endif
}

///////////////////////////////////////// code //////////////////////////////////////////////////////////////////////////
vector<ll> primes;
vector<bool> is_prime(1000001, true);
void sieve()
{
  is_prime[0] = is_prime[1] = false;
  for (ll i = 2; i * i <= 1000000; i++)
  {
    if (is_prime[i])
    {
      for (ll j = i * i; j <= 1000000; j += i)
      {
        is_prime[j] = false;
      }
    }
  }
  for (ll i = 2; i <= 1000000; i++)
  {
    if (is_prime[i])
      primes.push_back(i);
  }
}
void solve()
{
  ll l, r, res = 0;
  string s;
  cin >> l >> r;
  cin >> s;
  l--;
  r--;
  sieve();
  //cout << primes.size() << el;
  for (int i = l; i <= r; i++)
  {
    string k = to_string(primes[i]);
    if (k.find(s) != string::npos)
      res++;
  }
  cout << res << el;
}

int main()
{
  sasa();

  ll t = 1, i = 1;
  // cin >> t;
  while (t--)
  {
    // cout << "test #" << i << ":\n";
    solve();
    i++;
    if (!t)
      break;
    // cout << "\n";
  }

  return 0;
}