#include<iostream>
#include<algorithm>
using namespace std;
int main() {
	int n,m, tmp = 0;

	cin >> n;
	m = n;
	m *= 10;
	while (m /= 10) {
		tmp += m % 10;
		tmp *= 10;
	}
	tmp /= 10;

	cout << max(n, tmp) << endl;

	return 0;
}