#include <bits/stdc++.h>
using namespace std;
namespace My_IO {
inline char read() {
  return getchar();
  static const int IN_LEN = 1000000;
  static char buf[IN_LEN], *s, *t;
  if (s == t) {
    t = (s = buf) + fread(buf, 1, IN_LEN, stdin);
    if (s == t) return -1;
  }
  return *s++;
}
template <class T>
inline void rd(T& x) {
  static bool iosig;
  static char c;
  for (iosig = false, c = read(); !isdigit(c); c = read()) {
    if (c == '-') iosig = true;
    if (c == -1) return;
  }
  for (x = 0; isdigit(c); c = read()) x = (x + (x << 2) << 1) + (c ^ '0');
  if (iosig) x = -x;
}
const int OUT_LEN = 10000000;
char obuf[OUT_LEN], *ooh = obuf;
inline void print(char c) {
  if (ooh == obuf + OUT_LEN) fwrite(obuf, 1, OUT_LEN, stdout), ooh = obuf;
  *ooh++ = c;
}
template <class T>
inline void print(T x) {
  static int buf[30], cnt;
  if (x == 0)
    print('0');
  else {
    if (x < 0) print('-'), x = -x;
    for (cnt = 0; x; x /= 10) buf[++cnt] = x % 10 + 48;
    while (cnt) print((char)buf[cnt--]);
  }
}
inline void flush() { fwrite(obuf, 1, ooh - obuf, stdout); }
}  // namespace My_IO
using namespace My_IO;
const int N = 5E5 + 10;
int n, m, sa = 0, sb = 0;
char a[N], b[N];
int nxt[N];
int main() {
  scanf("%s", a + 1);
  scanf("%s", b + 1);
  n = strlen(a + 1);
  m = strlen(b + 1);
  for (int i = 1; i <= n; i++)
    if (a[i] == '0')
      sa++;
    else
      sb++;
  for (int i = 2; i <= m; i++) {
    int t = nxt[i - 1];
    while (t && b[t + 1] != b[i]) t = nxt[t];
    nxt[i] = t + (b[t + 1] == b[i]);
  }
  int na = 0, nb = 0;
  for (int i = 1; i <= nxt[m]; i++) {
    if (b[i] == '0')
      na++;
    else
      nb++;
  }
  if (na > sa || nb > sb) {
    puts(a + 1);
    return 0;
  }
  for (int i = 1; i <= nxt[m]; i++) {
    printf("%c", b[i]);
  }
  sa -= na, sb -= nb;
  na = nb = 0;
  for (int i = nxt[m] + 1; i <= m; i++) {
    if (b[i] == '0')
      na++;
    else
      nb++;
  }
  while (1) {
    if (sa < na || sb < nb) break;
    for (int i = nxt[m] + 1; i <= m; i++) {
      printf("%c", b[i]);
    }
    sa -= na, sb -= nb;
  }
  while (sa--) printf("0");
  while (sb--) printf("1");
  return 0;
}
