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#include <iostream>
#include <cmath>

long long k, N;
bool tmp_p[99];
short p[99];

short *sequence;
long long *partialValues;
int from, to, changeIndex, len;
bool stop;

void decreaseVal() {
    while(sequence[changeIndex] == 0) {
        changeIndex--;
    }
    sequence[changeIndex]--;
    for(int i=changeIndex; i < len; ++i) {
        if (i == 0) {
            partialValues[i] = p[sequence[i]];
        } else {
            partialValues[i] = partialValues[i - 1] * p[sequence[i]];
        }
    }
}

void enlargeSequence() {
    if (len == to) {
        stop = true;
    } else {
        sequence[len] = sequence[len - 1];
        partialValues[len] = partialValues[len - 1] * p[sequence[len]];
        len++;
    }
}

int main() {
    std::cin >> k;
    std::cin >> N;
    
    for(int i=0; i<k; ++i) {
        short tmp;
        std::cin >> tmp;
        tmp_p[tmp - 2] = true;
    }
    int pCount = 0;
    for(int i=0; i<99; ++i) {
        if (tmp_p[i]) {
          p[pCount++] = i + 2;  
        }
    }
    
    double logN = std::log(N);
    from = logN / std::log(p[pCount - 1]);
    to = logN / std::log(p[0]);
    
    sequence = new short[to];
    partialValues = new long long[to];
    for (int i=0; i<from; ++i) {
        sequence[i] = pCount -1;
        if (i == 0) {
            partialValues[i] = p[pCount - 1];
        } else {
            partialValues[i] = partialValues[i -1] * p[pCount -1];
        }
    }
    long long max = 0;
    len = from;
    stop = false;
    while(!stop) {
        changeIndex = len - 1;
        while(partialValues[len - 1] > N) {
            decreaseVal();
        }
        if (partialValues[len - 1] == N) {
            std::cout<< partialValues[len - 1];
            return 0;
        }
        if (max < partialValues[len - 1]) {
            max = partialValues[len - 1];
        }
        enlargeSequence();
    }
    
    std::cout << max;
    return 0;
}