#include <fstream>
using namespace std;
 
int findN(int p) {
    int i = 0;

    if (p == 0)
        return 1;

    while (p > 0) {
        i = i + 5;
        p--;
        if (i % 25 == 0)
            p--;
    }

    if (p < 0)
        return -1;

    return i;
}

int main() {
    ifstream fin("fact.in");
    ofstream fout("fact.out");
    int p;
    fin>>p;
    fout<<findN(p);
    return 0;
}