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#include <algorithm>
#include <iostream>
#include <vector>
#include <queue>
#include <cassert>
#include <cmath>

constexpr int64_t INF = int64_t(1e18)+5;
constexpr int N_SETS = 4;

struct Pair {
	int a, b;
	int64_t val;

	bool operator<(const Pair& r) const { return val < r.val; }
	bool operator>(const Pair& r) const { return val > r.val; }
};

int64_t nPrimes, limit;
std::vector<int64_t> allPrimes, primes[N_SETS];
std::vector<int64_t> elems[N_SETS];
double balance[N_SETS];

std::priority_queue<Pair, std::vector<Pair>, std::greater<Pair>> lowQue;
std::priority_queue<Pair> highQue;

inline int64_t safeMult(int64_t a, int64_t b) {
	constexpr int64_t OVER = 1ll << 31;
	if (a >= OVER && b >= OVER) {
		return INF;
	}
	if (((a >> 31)*b + (b >> 31)*a) >= OVER) {
		return INF;
	}

	int64_t c = a*b;
	return (c <= limit ? c : INF);
}

void compute(int part, int64_t current, int since) {
	elems[part].push_back(current);

	for (unsigned i = since; i < primes[part].size(); i++) {
		int64_t next = safeMult(current, primes[part][i]);
		if (next <= limit) {
			compute(part, next, i);
		}
	}
}

void popQueLow() {
	Pair top = lowQue.top();
	lowQue.pop();

	int a = top.a, b = top.b+1;
	if (b >= int(elems[1].size())) {
		return;
	}

	int64_t mult = safeMult(elems[0][a], elems[1][b]);
	if (mult <= limit) {
		lowQue.push(Pair{a, b, mult});
	}
}

void popQueHigh(int64_t low) {
	Pair top = highQue.top();
	highQue.pop();
	
	int a = top.a, b = top.b;

	while (--b >= 0) {
		int64_t tmp = elems[2][a]*elems[3][b];
		if (safeMult(low, tmp) <= limit) {
			highQue.push(Pair{a, b, tmp});
			break;
		}
	}
}

int main() {
	std::ios::sync_with_stdio(false); std::cin.tie(0);
	std::cin >> nPrimes >> limit;

	allPrimes.resize(nPrimes);
	for (auto& p : allPrimes) {
		std::cin >> p;
	}

	// Partition (good enough)

	sort(allPrimes.begin(), allPrimes.end());
	for (auto& x : balance) {
		x = 0.0;
	}

	for (auto p : allPrimes) {
		int best = 0;
		for (int i = 1; i < N_SETS; i++) {
			if (balance[i] < balance[best]) {
				best = i;
			}
		}

		primes[best].push_back(p);
		balance[best] += 1 / (std::log(p)+1);
	}

	// Compute partial results

	for (int i = 0; i < N_SETS; i++) {
		compute(i, 1, 0);
		sort(elems[i].begin(), elems[i].end());
	}

	// Init queues

	for (unsigned i = 0; i < elems[0].size(); i++) {
		int64_t mult = safeMult(elems[0][i], elems[1][0]);
		if (mult <= limit) {
			lowQue.push(Pair{int(i), 0, mult});
		}
	}

	int j = elems[3].size()-1;

	for (unsigned i = 0; i < elems[2].size(); i++) {
		int64_t lowVal = elems[2][i], cur = 0;

		while (j >= 0) {
			cur = safeMult(lowVal, elems[3][j]);
			if (cur <= limit) {
				break;
			}
			j--;
		}

		if (cur <= 0) {
			assert(j < 0);
			break;
		}
		highQue.push(Pair{int(i), j, cur});
	}

	// Combine

	int64_t best = 1;

	while (!lowQue.empty() && !highQue.empty()) {
		int64_t lowVal = lowQue.top().val, cur = 0;

		while (!highQue.empty()) {
			cur = safeMult(lowVal, highQue.top().val);
			if (cur <= limit) {
				break;
			}
			popQueHigh(lowVal);
		}

		best = std::max(best, cur);
		popQueLow();
	}

	std::cout << best << std::endl;
	return 0;
}