#include<bits/stdc++.h>
using namespace std;
#include <stdio.h>
#include <math.h>
#include <x86intrin.h>
#define ll long long

bool pr[131313131313131314]={};

void a(){
pr[1]=true;
ll a,b;
a=2;
while(a<140000000){
while(pr[a])++a;
for(b=2*a;b<131313131313131314;b+=a)pr[b]=true;
++a;
}}

int main(){
    ll n,i,p=1,ans,j,k,l;
    cin>>n;
    int ba[n];
    int t[3*n];
    t[1]=1;
    for(i=2;i-3*n;++i)t[i]=t[i-1]*10;
    for(i=0;i-n;++i)cin>>ba[i],p*=2;
    ll s[512]={},m=0;
    a();
    for(i=0;i-p;++i){
         k=i;
         ans=ba[0];
         l=ba[0]>9?2:1;
         for(j=1;j-n;++j){
             l+=ba[j]>9?2:1;
             if(k%2)ans+=ba[j]*t[l];
             else{ans*=ba[j]>9?100:10;ans+=ba[j];}
             k/=2;}
         if(!pr[ans])s[m++]=ans;}
    int max=0;
    for(i=0;i-512;++i)max=max>s[i]?max:s[i];
    if(max)cout<<max<<"\n";
    else cout<<"No"<<"\n";
}