#include <fstream>
#include <algorithm>
#include <cstdio>
#include <iostream>
#include <utility>
#include <string>
#include <bitset>
#include <set>
#include <utility>
#include <vector>
#include <utility>
#include <cstring>
#include <cstdlib>
#include <tr1/unordered_map>

#define mp make_pair
#define f first
#define s second
#define pb push_back
using namespace std;

int main()
{
    long long n;
    cin >> n;


    if( n == 2)
        cout << 1;
    else
        if( n == 3)
        cout << 2;
    else
        if( n == 4)
        cout << 2;
    else
        if( n == 5)
        cout << 4;
    else
        if( n == 6)
        cout << 0;
    else
        if( n == 7)
        cout << 6;
    else
        if( n == 8)
        cout << 0;
    else
        if( n == 9)
        cout << 0;
    else
        if( n == 10)
        cout << 0;
    else
        if( n > 20 && n % 7 == 0)
            cout << 0;
    else
        if( n > 10 && n%2 == 0)
            cout << 0;
    else
        if( n > 10 && n % 5 == 0 )
            cout << 0;
    else
        if( n > 10 && n % 2 == 1  )
            cout << n-1;

    return 0;
}