#include<bits/stdc++.h>
using namespace std;
int main(){
   	int a,s,d,f;
   	cin>>a;
    s=a%10;
    d=a/10%10;
    f=a/100;
    if(f>d){
    	swap(f,d);
	}
	if(f>s){
		swap(f,s);
	}
	if(d>s){
		swap(d,s);
	}cout<<f<<d<<s;
  }
/**************************************************************
	Problem: 1243
	User: tonghuawei
	Language: C++
	Result: Wrong Answer
****************************************************************/