# include <fstream>
# include <iostream>
# include <algorithm>
using namespace std;
int n, k, v[103], p[103], ex[103], sol[500000];

void read ()
{
	ifstream fin ("factoriale.in");
	fin>>n>>k;
	for(int i=1;i<=n;++i)
		fin>>v[i];
}

void prime ()
{
	p[1]=2;
	p[0]=1;
	int pp;
	for(int i=3;i<=100;i+=2)
	{
		pp=1;
		for(int j=1;j<=p[0] && pp;++j)
			if(i%p[j]==0)
				pp=0;
		if (pp)
			p[++p[0]]=i;
	}
}

void inm (int n)
{
	int q, t=0;
	for(int i=1;i<=sol[0];++i)
	{
		q=n*sol[i]+t;
		sol[i]=q%10;
		t=q/10;
	}
	while(t)
	{
		sol[++sol[0]]=t%10;
		t/=10;
	}
}

void solve ()
{
	int poz=1, nr;
	for (int i=1;i<=n;++i)
		for(int k=1;k<=v[i];++k)
		{
			nr=k;
			for(int j=1;nr>1;++j)
				while (nr%p[j]==0)
				{
					++ex[j];
					nr/=p[j];
				}
		}
	sol[0]=sol[1]=1;
	for(int i=1;i<=p[0];++i)
		if (ex[i]%k)
			for(int j=1;j<=k-ex[i]%k;++j)
				inm(p[i]);
}

int main ()
{
	read ();
	prime ();
	solve ();
	ofstream fout ("factoriale.out");
	for(int i=sol[0];i;--i)
		fout<<sol[i];
	return 0;
}