#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <string>
#define inf 1e9+1
using namespace std;
ifstream fin("adn.in");
ofstream fout("adn.out");
vector<string>v;
int n;
const int NMAX = 17;
int c[NMAX][NMAX];
const int NMAX2 = (1 << (NMAX+1)) + 2;
int dp[NMAX][NMAX2];
//dp[i][mask] = lungimea minima a unui sir pe care putem forma stiinda ca ultimul sir gasit ca si potrivire este sirul i si avem deja sirurile din mask acoperite
void removeUselessElements() {
    vector<int>removeElements;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            if (i != j && v[i].size() >= v[j].size()) {
                if (v[i].find(v[j]) != string::npos) {
                    removeElements.push_back(j);
                }
            }
        }
    }
    sort(removeElements.begin(), removeElements.end());
    removeElements.erase(unique(removeElements.begin(), removeElements.end()), removeElements.end());
    for (int i = removeElements.size() - 1; i >= 0; --i) {
        v.erase(v.begin() + removeElements[i]);
    }
}

int calcLungComun(string& s) {
    vector<int>pi(s.size() + 1);
    pi[1] = 0;
    int k = 0;
    for (int i = 2; i <= s.size(); ++i) {
        while (k != 0 && s[k] != s[i - 1]) {
            k = pi[k];
        }
        if (s[k] == s[i - 1]) {
            k++;
        }
        pi[i] = k;
    }
    return pi[s.size()];
}
void calcC() {
    string aux;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            aux = v[j] + '%' + v[i];
            c[i][j] = v[j].size() - calcLungComun(aux);
          //  fout << i << " " << j << " " << c[i][j]<<endl;
        }
    }
}
void calcDp() {
    for (int i = 0; i < NMAX; ++i) {
        for (int j = 0; j < NMAX2; ++j) {
            dp[i][j] = inf; 
        }
    }
    for (int i = 0; i < n; ++i) {
        dp[i][1 << i] = v[i].size();//lungimea propriilor siruri e lungimea insasi
    }
    for (int m = 1; m <= (1 << n); ++m) {
        for (int i = 0; i < n; ++i) {
            if (m & (1 << i)) {//daca i  face parte din masca curenta
                for (int j = 0; j < n; ++j) {
                    if (!(m & (1 << j))) {//daca nu l-am inclus deja pe j
                        //il adugam pe j la masca curenta
                        int nextMask = m + (1 << j);
                        dp[j][nextMask] = min(dp[j][nextMask], dp[i][m] + c[i][j]);
                    }
                }
            }
        }
    }
}
void getResult() {
    int rez=inf;
    int lastMask = (1 << n) - 1;
    int lastIndex;
    for (int i = 0; i < n; ++i) {
        if (rez > dp[i][lastMask]) {
            rez = dp[i][lastMask];
            lastIndex = i;//ultimul indice care face parte din masca
        }
    }
    vector<int> indexStrings;
    indexStrings.push_back(lastIndex);
    for(int i=1;i<n;++i) {
        int nextMask = lastMask - (1 << lastIndex);
        for (int j = 0; j < n; ++j) {
            if (nextMask & (1 << j) && j!=lastIndex) {
                if (dp[lastIndex][lastMask] == dp[j][nextMask] + c[j][lastIndex]) {//daca j e urmatoarul string din permutare
                   // cout << "test!!!!";
                    lastMask = nextMask;
                    lastIndex = j;
                    indexStrings.push_back(j);
                    j = n;
                }
            }

        }
    }
    //cout << indexStrings.size() << endl;
    reverse(indexStrings.begin(), indexStrings.end());


    fout << v[indexStrings[0]];
    for (int i = 1; i < indexStrings.size(); ++i) {
        int ant = indexStrings[i - 1];
        int crt = indexStrings[i];
        int intersectie = v[crt].size()-c[ant][crt];
        for (int j = intersectie; j < v[crt].size(); ++j) {
            fout << v[crt][j];
        }
    }

    return ;
}
int main()
{
    fin >> n;
    v.resize(n);
    for (int i = 0; i < n; ++i) {
        fin >> v[i];
    }
    removeUselessElements();
    n = v.size();
    calcC();
    calcDp();
    getResult();
    return 0;
}
//=^..^=