include<bits/stdc++.h>

using namespace std;
long long a[123456789],res,n,t,dem,luong,s,minn,l,r,sum,mid;
long long lam(long long mid)
{
s=0;
for(int i=1;i<=n;i++)
s=s+(mid/a[i]);
return s;
}
int main()
{
minn=1e18;
l=1;
r=1e18;
cin>>n>>t;
for(int i=1;i<=n;i++)
cin>>a[i];
while(l<=r)
{
mid=(l+r)/2;
sum=lam(mid);
if(sum>=t){
res=mid;
r=mid-1;
}
else{
l=mid+1;
}
}
cout<<res;

}