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#include <stdio.h>
#include <stdlib.h>

int ok(int* p, int k, long long n, int has2, int has3, int has5) {
  int i;
  if ((!has2 && n%2==0) || (!has3 && n%3==0) || (!has5 && n%5==0))
    return 0==1;
  for (i=0;i<k;i++)
    while (n % p[i]==0)
      n /= p[i];
  return n==1;
}

int has(int* p, int k, int d) {
  int i;
  for (i=0;i<k;i++)
    if (p[i]==d)
      return 1==1;
  return 1==0;
}

int mklog(long long n, int p) {
  int s = 1;
  while (n>0) {
    n /= p;
    s++;
  }
  return s;
}

unsigned long long go_long(unsigned long long v, unsigned long long n, int* p, int k, int ix) {
  if (k==ix)
    return v;
  unsigned long long m = v;
  while (v<=n) {
    unsigned long long mm = go_long(v, n, p, k, ix+1);
    if (mm<=n && mm>m)
      m = mm;
    v *= p[ix];
  }
  return m;
}

int main() {
  int k, i, j;
  long long n;
  long long pp;
  int p[100];
  int mp[100];
  scanf("%d%lld", &k, &n);
  for (i=0;i<k;i++)
    scanf("%d", &p[i]);
  for (i=0;i<k;i++)
    mp[i] = mklog(n, p[i]);
  pp = 10000000;
  for (i=0;i<k;i++)
    pp /= mp[i];
  if (pp>0 || k<15) {
    unsigned long long vv = go_long(1, n, p, k, 0);
    printf("%llu\n", vv);
  } else {
    int has2 = has(p, k, 2);
    int has3 = has(p, k, 3);
    int has5 = has(p, k, 5);
  
    //unsigned long long vv = go_long(1, n, p, k, 0);
    //printf("%llu\n", vv);
    
    for (;n>=1;n--) {
      if (ok(p, k, n, has2, has3, has5)) {
        printf("%lld\n", n);
        return 0;
      }
    }
    printf("1\n");
  }
  return 0;
}