//  #### Zeinab
#include<bits/stdc++.h>
using namespace std;
#define nl "\n"
#define fi first
#define se second
#define pb push_back
#define ll long long
#define RV return void
#define sz(x) int(x.size())
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define cin(v) for(auto&x:v) cin >> x;
#define cout(v) for(auto&x:v) cout << x << " ";


const int N = 2e5 + 5 , MD = 1e9+7;
int p[2]= {31 , 37} , mod[2] = {MD , MD+2};
int pw[N][2] , inv[N][2];


int mul(int a , int b , int md){
    return (  1ll * a*b ) % md;
}
int add(int a , int b , int md){
    return ( a%md +b%md ) % md;
}
int fastPower(int a , int b , int md){
    int ret =1;
    while(b){
        if(b & 1 ) ret = mul( ret, a , md);
        a= mul(a , a , md );
        b>>=1;
    }
    return ret ;
}

void pre(){
    pw[0][0] = pw[0][1] = inv[0][0] = inv[0][1] =1;

    for(int j =0 ;j < 2 ; j++){
        int minv = fastPower(p[j] , mod[j]-2 , mod[j]);
        for(int i =1 ; i < N ; i++){
            pw[i][j] = mul(pw[i-1][j], p[j] , mod[j]);
            inv[i][j] = mul(inv[i-1][j] , minv , mod[j]);
        }
    }
}



struct hashing{
    vector < vector < int > > pref;

    hashing(string s , int n){
        pref.assign(n+1 , vector<int>(2));

        for(int j =0 ; j < 2 ; j++){
            for(int i =0 ; i < n ; i++){
                char c = 'a';
                if (s[i] >='A' and s[i] <='Z') c = 'A';
                // upper or lower
                int ch = s[i] - c + 1;
                pref[i][j] = mul(ch , pw[i][j] , mod[j]);
                if(i){
                    pref[i][j] = add(pref[i][j] , pref[i-1][j] , mod[j]);
                }
            }
        }
    }

    int calc(int l , int r , int step){
        int ret = pref[r][step];
        if(l){
            ret = (ret - pref[l-1][step] + mod[step]) % mod[step];
        }
        ret = mul(ret , inv[l][step] , mod[step]);
        return ret;
    }

    pair < int , int > get_Hash(int l , int r){
        return {calc(l,r,0) , calc(l,r,1)};
    }

};


bool palindrome(string & s , int l , int r){
    while(l <= r) {
        if (s[l] != s[r]) return false;
        l++ , r--;
    }
    return true;
}

void solve(){

    string s;
    while(cin >> s){
        int n = sz(s);
        if(palindrome(s, 0, n-1)){
            cout << s << nl;
            continue;
        }
        hashing m_hash(s,n);
        int added = 0 , curr1 = 0 , curr2=0, all_len=n ;

        while(added < n){
            all_len = n + added + 1;

            char c = 'a';
            if (s[added] >='A' and s[added] <='Z') c = 'A';
            int ch = s[added] - c + 1;
            curr1 = add(curr1 , mul(ch , pw[added][0] , mod[0]) , mod[0]);
            curr2 = add(curr2 , mul(ch , pw[added][1] , mod[1]) , mod[1]);
            int cnt = n-1 , curr1_temp =curr1, curr2_temp =curr2;

            int index = added+1;
            while(cnt >=(all_len)/2 ){
                c = 'a';
                if (s[cnt] >='A' and s[cnt] <='Z') c = 'A';
                ch = s[cnt] - c + 1;

                curr1_temp = add(curr1_temp , mul(ch , pw[index][0] , mod[0]) , mod[0]);
                curr2_temp = add(curr2_temp , mul(ch , pw[index][1] , mod[1]) , mod[1]);

                index++ , cnt--;
            }


            if(make_pair(curr1_temp , curr2_temp) == m_hash.get_Hash(0,(all_len)/2 )){
                cout << s ;
                for(int i = added ; i >=0 ; i--) cout << s[i] ;
                cout << nl;
                break;
            }
            added++;
        }
    }

}
// amanaplanacanalpanama

int main(){
    ios_base::sync_with_stdio(false),cin.tie(nullptr),cout.tie(nullptr);

    int t=1;
        // cin >> t ;
    pre();
    for(int i=1 ; i <= t ; i++){
        // cout << "Case #"<< i <<": ";
        solve();
    }
    return 0;
}