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#include <cstdio>
#include <vector>

typedef long long (*FastDivision)(long long);

template<int n>
long long FastDivisionImpl(long long value) { return value/n; }

template<int n, int len=n>
struct Division : Division<n-1, len>
{
    Division<n, len>()
    {
        this->ops[n] = &FastDivisionImpl<n>;
    }
};

template<int len>
struct Division<0, len>
{
    FastDivision ops[len+1];
    long long operator() (long long a, int b) { return ops[b](a); }
};

Division<100> div;


std::vector<int> primes;
long long answer = 1;

void solve(long long N, int const *p, long long current_answer=1)
{
    //printf("  solve(%lld, %d, %lld)\n", N, *p, current_answer);
    if (N * current_answer <= answer)
        return;

    if (*p == 0) 
        return;

    if (current_answer > answer)
        answer = current_answer;

    if (N >= *p)
        solve(div(N, *p), p, current_answer * *p);

    solve(N, p+1, current_answer);
}


int main()
{
    int k;
    long long N;
    scanf("%d %lld", &k, &N);

    primes.resize(k);
    for(auto &p : primes)
        scanf("%d", &p);
    primes.push_back(0);

    solve(N, primes.data());

    printf("%lld\n", answer);
}