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#include <iostream>
#include <algorithm>    // std::fill
#include <vector>       // std::vector
#include <iterator>
using namespace std;
 
// class generator:
struct c_unique {
  int current;
  c_unique() {current=0;}
  int operator()() {return ++current;}
} UniqueNumber;
 
template <typename T>
std::ostream& operator<< (std::ostream& out, const std::vector<T>& v) {
  if ( !v.empty() ) {
    //out << "["
    std::copy (v.begin(), v.end(), std::ostream_iterator<T>(out, " "));
    //out << "\b\b]";
  }
  return out;
}

#include <functional>

#include <numeric>

long long int branchnbound(
	const vector<int> &seq,
	long long int N
	//, std::function<long long int(vector<int>&)> calcfnc
	//, std::function<bool(vector<int>&, long long int curval)> cutbranchfnc
	) {
	int product = std::accumulate(seq.begin(), seq.end(), 1, std::multiplies<int>());
	//cout<<seq<<" = "<<product<<endl;
	if(product <= N) {
		return product;
	} else {
		long long int acc = 1;
		for(auto el : seq) {
			vector<int> seq2(seq);
			seq2.erase(remove(seq2.begin(), seq2.end(), el), seq2.end());
			long long int res = branchnbound(seq2, N);
			if(res>N) res = 1;
			acc = max(acc, res);
		}
		return acc;
	}
}

int main() {
	long long int n, k;
	std::ios::sync_with_stdio(false);
	cin.tie(NULL);
	cin >> n >> k;
	vector<int> vec;
	while(cin>>n) vec.push_back(n);
	
	// #define UNIQUE 
	#ifdef UNIQUE // += O(n^2)
	std::sort(vec.begin(), vec.end());
	auto last = std::unique(vec.begin(), vec.end());
	vec.erase(last, vec.end()); 
	#endif
    
	cout<<branchnbound(vec, k)<<endl;
	return 0;
}