/**
 *  - Meet Brahmbhatt
 *  - Hard work always pays off
**/
#include"bits/stdc++.h"
using namespace std;

#ifdef MeetBrahmbhatt
#include "debug.h"
#else
#define dbg(...) 72
#endif

#define endl "\n"
#define int long long

const long long INF = 4e18;

void solve() {
    string S, A;
    cin >> S >> A;
    A = '_' + A;
    int x;
    cin >> x;
    while (x--) {
        S += A;
    }
    cout << S;
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed << setprecision(9);
    int tt = 1;
    // cin >> tt;
    while (tt--) solve();
    return 0;
}