#include <iostream>
using namespace std;
int main() {
int n;
cin >> n;
int pc, mc, uc;
uc = n % 10;
mc = n % 100 / 10;
pc = n / 100;
int i = 9, nr = 0;
while(i >= 0 && nr < 3) {
if(uc == i) {
cout << i;
nr++;
}
if(pc == i){
cout << i;
nr++;
}
if(mc == i){
cout << i;
nr++;
}
i--;
}
return 0;
}