#include <fstream>
#include <algorithm>
using namespace std;
ifstream fi("economie.in");
ofstream fo("economie.out");
int V[1001];
int n;
int REZ[1001],rez;
int P[50001];
int main()
{
    fi>>n;
    for(int i=1;i<=n;i++)
        fi>>V[i];
    sort(V+1,V+n+1);
    P[0]=1;
    for(int i=1;i<=n;i++)
        if(P[V[i]]==0)
        {
            REZ[++rez]=V[i];
            for(int j=0;j<=50000;j++)
                if(P[j]==1 && j+V[i]<=50000)
                    P[j+V[i]]=1;
        }
    fo<<rez<<"\n";
    for(int i=1;i<=rez;i++)
        fo<<REZ[i]<<"\n";
    fi.close();
    fo.close();
    return 0;
}