#include <fstream>
#include <cmath>
using namespace std;
long long n,i,nr2,nr5,aux;
ifstream f("fact.in");
ofstream g("fact.out");
int main()
{
f>>n;
for(i=1;i<=pow(10,8);i++)
    {
        aux=i;
        while(aux%2==0)
            {aux/=2;
        nr2++;}
        while(aux%5==0)
        {
            aux/=5;
            nr5++;
        }
        if(nr5==n)
            {g<<i;
        break;}
    }
return 0;
}