#include "bits/stdc++.h"
using namespace std;
namespace util {
using ll = long long;
using vl = std::vector<long long>;
using pl = std::pair<long long, long long>;

constexpr long long kInf = std::numeric_limits<long long>::max() / 8;
constexpr long long kMax = std::numeric_limits<long long>::max();

template <typename T, typename U>
inline bool UpdateMax(T &x, const U &y) {
  if (x < y) {
    x = y;
    return true;
  }
  return false;
}

template <typename T, typename U>
inline bool UpdateMin(T &x, const U &y) {
  if (x > y) {
    x = y;
    return true;
  }
  return false;
}

// verified
inline long long Pow(long long x, long long n) {
  assert(n >= 0);
  if (x == 0) return 0;
  long long res = 1LL;
  while (n > 0) {
    if (n & 1) {
      assert(x != 0 && std::abs(res) <= kMax / std::abs(x));
      res = res * x;
    }
    if (n >>= 1) {
      assert(x != 0 && std::abs(x) <= kMax / std::abs(x));
      x = x * x;
    }
  }
  return res;
}

// verified
inline long long Mod(long long n, const long long m) {
  // returns the "arithmetic modulo"
  // for a pair of integers (n, m) with m != 0, there exists a unique pair of
  // integer (q, r) s.t. n = qm + r and 0 <= r < |m| returns this r
  assert(m != 0);
  if (m < 0) return Mod(n, -m);
  if (n >= 0)
    return n % m;
  else
    return (m + n % m) % m;
}

inline long long Quotient(long long n, long long m) {
  // returns the "arithmetic quotient"
  assert((n - Mod(n, m)) % m == 0);
  return (n - Mod(n, m)) / m;
}

inline long long DivFloor(long long n, long long m) {
  // returns floor(n / m)
  assert(m != 0);
  if (m < 0) {
    n = -n;
    m = -m;
  }
  if (n >= 0)
    return n / m;
  else if (n % m == 0)
    return -(abs(n) / m);
  else
    return -(abs(n) / m) - 1;
}

inline long long DivCeil(long long n, long long m) {
  // returns ceil(n / m)
  assert(m != 0);
  if (n % m == 0)
    return DivFloor(n, m);
  else
    return DivFloor(n, m) + 1;
}

template <typename T>
inline T Sum(const std::vector<T> &vec) {
  return std::accumulate(vec.begin(), vec.end(), T(0));
}
}  // namespace util
using namespace util;

void solve() {
  string s, t;
  cin >> s >> t;
  ll n;
  cin >> n;
  for (ll i = 0; i < n; ++i) {
    s += "_" + t;
  }
  cout << s << '\n';
}

int main() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
  std::cout << std::fixed << std::setprecision(15);

  solve();

  return 0;
}