#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("economie.in");
ofstream fout("economie.out");
int n,i,j,t,ok,nr,S[50000001],V[1001];
int main()
{fin>>n;
for(i=1;i<=n;i++)
    fin>>V[i];
sort(V+1,V+n+1);
for(i=1;i<=n;i++){
    S[V[i]]=1;
    for(j=1;j<=V[n];j++)
        if(S[j]!=0)
           S[j+V[i]]=1;
    ok=1;
    nr=i;
    for(t=i+1;t<=n;t++)
        if(S[t]==0){
           ok=0;
           break;}
    if(ok==1)
       break;
}
fout<<i<<"\n";
for(i=1;i<=nr;i++)
    fout<<V[i]<<"\n";







    return 0;
}