#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <queue>
#include <cmath>
#include <climits>
#include <iomanip>
#include <set>
#include <map>
using namespace std;
typedef long long ll;
int main(){
    string s;
    cin >> s;
    if(s == "0")cout << s << endl;
    else cout << s << "0" << endl;
}