#include <iostream>
#include <vector>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
	string s;
	cin >> s;
	vector <char> c;
	for (auto e : s)
		c.push_back(e);


	sort(c.begin(), c.end());

	int i = 0;
	while (i < c.size() && c[i] == '0') ++i;

	if (c.front()!='0')
		for (auto e : c) cout << e;
	else
	{
		int j = i;
		cout << c[j];
		++j;
		//while (j < c.size() && c[j] == c[i]) { cout << c[j]; ++j; }
		--i;
		while (i>=0) { cout << c[i]; --i; }
		while (j < c.size()) { cout << c[j]; ++j; }
	}

	return 0;
}