#include <bits/stdc++.h>
using namespace std;
int main(){
	string s;
	cin >> s;
	int l, r = s.size() - 1;
	for(int i = 0; i < s.size(); i++){
		if(s[i] == '1'){
			l = i;
			break;
		}
	}
	while(s[r] == '1'){
		while(s[r] == '1' && s[r-1] == '0')
			r -= 1;
		while(s[r-1] == '1')
			r -= 2;
	}
// 	cout << "L: " << l << "\nR: " << r << "\n";
	while(l < r)
	{
		char tot = s[r];
		s[r] = s[l];
		s[l] = tot;
		l++;
		r--;
	}
	cout << s;
	return 0;
}

打了60分，只因本人是小学生