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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

bool prime[1000005];
bool visited[1000005];
int main() {
    long long million = 1e6;
    for(int i = 0; i <= million; i++) {
        prime[i] = true;
        visited[i] = false;
    }
    prime[0] = false;
    prime[1] = false;
    
    for(long long i = 2; i <= million; i++) {
        if(prime[i]) {
            for(long long j = i * i; j <= million; j += i) {
                prime[j] = false;
            }
        }
    }
    string s;
    cin >> s;
    int primes = 0;
    for(int i = 0; i < (int) s.size(); i++) {
        string tmp = "";
        for(int j = i; j < i + 6 and j < (int) s.size(); j++) {
            tmp += s[j];
            int x = 0;
            for(int k = 0; k < (int) tmp.size(); k++) {
                x = (x * 10) + (tmp[k] - '0');
            }
            if(prime[x] and !visited[x]) {
                visited[x] = true;
                primes++;
            }
        }
    }
    cout << primes << endl;
    return 0;
}