//c++ program to sort characters
// Time complexity is O(log n)
//Space complexity is O(n)
#include<iostream>
#include<bits/stdc++.h>
#include<algorithm>
#include<vector>
int main()
{
vector<char> v;
char ch;
for(int i=1;i<=1000;i++)
cin>>ch,v.push_back(ch);
sort(v.begin(),v.end());
cout<<"\n Sorted character array is\n";
for(vector<char>::iterator it=v.begin();it!=v.end();it++)
cout<<*it;
return 0;
}