#include "bits/stdc++.h"
#define MOD 1000000007
#define INF 11234567890
#define in std::cin
#define out std::cout
#define rep(i,N) for(int i=0;i<N;++i)
typedef long long int LL;

std::string S;

int main()
{
	in >> S;
	if (S == "0") { out << S << std::endl; }
	else out << S << "0" << std::endl;
	return 0;
}