#include <stdio.h>
# define N 1128
#define M 50128
int rez[N],v[N];
int val[M];
int main()
{
	int r=0,n,i,j;
	int inj,gata,aux;
	freopen("economie.in", "r",stdin);
	freopen("economie.out", "w",stdout);
	scanf("%d", &n);
	for(i=1;i<=n;++i)
			scanf("%d", &v[i]);
	inj=n; while(inj>1)
	{inj/=2; do{gata=1;
	for(i=1;i<=n-inj;i++)
	if(v[i]>v[i+inj])
	{aux=v[i]; v[i]=v[i+inj];
	v[i+inj]=aux; gata=0;}
	}while(!gata); 	}
	
	val[0]=1;
	for(i=1;i<=n;++i)
	{
		if(!val[v[i]])
		{	
			for(j=0;j<M-v[i];++j)
				if(val[j])
					val[j+v[i]]=1;
			rez[++r]=v[i];
		}
	}
	printf("%d\n", r);
	for(i=1;i<=r;++i)
		printf("%d\n", rez[i]);
	return 0;
}