#include <bits/stdc++.h>
using namespace std;
const int inf = 0x3f3f3f3f;
const double pi = 3.1415926535897932384626;
inline long long read() {
  long long x = 0, f = 1;
  char ch = getchar();
  while (ch < '0' || ch > '9') {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (ch >= '0' && ch <= '9') {
    x = (x << 1) + (x << 3) + (ch ^ 48);
    ch = getchar();
  }
  return x * f;
}
const int maxn = 5e5 + 5;
int len1, len2, nxt[maxn];
string s1, s2, ans;
void getnext() {
  nxt[0] = -1;
  int k = -1, j = 0;
  while (j < len2) {
    if (k == -1 || s2[j] == s2[k])
      nxt[++j] = ++k;
    else
      k = nxt[k];
  }
}
int main() {
  cin >> s1 >> s2;
  len1 = s1.length(), len2 = s2.length();
  getnext();
  int cnt0 = 0, cnt1 = 0;
  for (int i = 0; i < len1; ++i) {
    if (s1[i] == '0')
      ++cnt0;
    else
      ++cnt1;
  }
  int i = 0;
  while (cnt0 && cnt1) {
    if (s2[i] == '0') {
      if (cnt0) {
        ans += '0';
        --cnt0;
      } else
        break;
    } else if (s2[i] == '1') {
      if (cnt1) {
        ans += '1';
        --cnt1;
      } else
        break;
    }
    ++i;
    if (i == len2 + 1) i = nxt[len2];
  }
  cout << ans;
  while (cnt0) {
    printf("0");
    --cnt0;
  }
  while (cnt1) {
    printf("1");
    --cnt1;
  }
  printf("\n");
  return 0;
}
