#include <bits/stdc++.h>
const char dl = '\n';
const long double eps = 0.00000001;
const long long MOD = 1e9 + 7;
const long long mod = 998244353;
const double PI = 3.141592653589793238463;
const long double pi = 4 * atan(1.0);
using namespace std;
void debug() { cout << endl; }
template <typename H, typename... T>
void debug(H p, T... t) {
  std::cout << p << " ";
  debug(t...);
}
string second, t, res;
int ans;
int n, m, k;
stack<char> STACK;
deque<char> DEQUE;
queue<char> QUEUE;
map<char, int> cnts, cntt, need;
vector<int> z_function(string second) {
  int n = (int)second.length();
  vector<int> z(n);
  for (int i = 1, l = 0, r = 0; i < n; ++i) {
    if (i <= r) z[i] = min(r - i + 1, z[i - l]);
    while (i + z[i] < n && second[z[i]] == second[i + z[i]]) ++z[i];
    if (i + z[i] - 1 > r) l = i, r = i + z[i] - 1;
  }
  return z;
}
int main() {
  fflush(stdin);
  cout << fixed, cout.precision(18);
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int i, j;
  cin >> second >> t;
  int m = (int)t.size(), n = (int)second.size();
  vector<int> z = z_function(t);
  int mx = 0;
  for (i = 0; i < m; ++i) {
    if (i + z[i] == m) mx = max(mx, z[i]);
  }
  string mask = "";
  if (!mx)
    mask = t;
  else {
    int r = m - 1;
    for (i = 0; i < m - mx; ++i) mask += t[r--];
    reverse(mask.begin(), mask.end());
  }
  for (auto it : t) cntt[it]++;
  for (auto it : second) cnts[it]++;
  for (auto it : mask) need[it]++;
  if (cnts['1'] >= cntt['1'] && cnts['0'] >= cntt['0']) {
    res += t;
    cnts['1'] -= cntt['1'];
    cnts['0'] -= cntt['0'];
  }
  while (true) {
    if (cnts['1'] >= need['1'] && cnts['0'] >= need['0']) {
      res += mask;
      cnts['1'] -= need['1'];
      cnts['0'] -= need['0'];
    } else
      break;
  }
  for (i = 0; i < cnts['1']; ++i) res += '1';
  for (i = 0; i < cnts['0']; ++i) res += '0';
  cout << res << endl;
}
