#include <iostream>
#include <string>
#include <cctype>
#include <algorithm>
 
using namespace std;
 
int main() {
    string input;
    getline( cin, input );
    stable_sort( input.begin(), input.end(), 
                 []( char c1, char c2 )
                 {
                 	return isalpha( c1 ) && !isalpha( c2 );
                 } );
    cout << input;
    return 0;
}