#include <bits/stdc++.h>
using namespace std;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}
using Int = long long;
const char newl = '\n';


template<typename F>
struct FixPoint : F{
  FixPoint(F&& f):F(forward<F>(f)){}
  template<typename... Args>
  decltype(auto) operator()(Args&&... args) const{
    return F::operator()(*this,forward<Args>(args)...);
  }
};
template<typename F>
inline decltype(auto) MFP(F&& f){
  return FixPoint<F>{forward<F>(f)};
}

//INSERT ABOVE HERE
signed main(){
  cin.tie(0);
  ios::sync_with_stdio(0);

  int n,k;
  cin>>n>>k;
  vector<int> as(n);
  for(int i=0;i<n;i++) cin>>as[i];

  sort(as.rbegin(),as.rend());

  int ans=0;
  MFP([&](auto dfs,int i,int x)->void{
    if(i==n){
      chmax(ans,x%as.back());
      return;
    }
    dfs(i+1,x);
    dfs(i+1,x%as[i]);
  })(0,k);

  cout<<ans<<newl;
  return 0;
}