#include <fstream>

using namespace std;
ifstream fin ("fact.in");
ofstream fout ("fact.out");
int p,N,ok,aux;
int main()
{
    fin>>p;
    do {
        N+=5;
        if(N%10==0)
        {
            aux=N;
            while(aux%10==0)
            {
                aux/=10;
                ok++;
            }
        }
        else
            ok++;
    }while(ok<p);
    fout<<N;
    return 0;
}