#include <fstream>

using namespace std;

ifstream cin("fact.in");
ofstream cout("fact.out");

int p;
int n=1;

int main(){
    cin>>p;
    if(p==0){
        cout<<1;
        return 0;
    }
    for(n=5;p;n+=5){
        int cn = n;
        while(n%5==0)
            p--,n/=5;
        n = cn;
        if(p==0)
            cout<<cn;
    }


}