#include <bits/stdc++.h>
using namespace std;
// #include<atcoder/all>
// using mint = atcoder::modint998244353;
using ld = long double;
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define rep(i,n) for(int i=0;i<(int)(n);++i)
#define chmax(a,b) a=max(a,b)
#define chmin(a,b) a=min(a,b)

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    string S;
    cin>>S;
    string a,b;
    for(char c: S){
        if('a'<=c&&c<='z')a+=c;
        else b+=c;
    }
    reverse(all(a));
    cout<<a<<b<<"\n";
}