//将砝码质量分为1 2 4 -1 -2 -4就能够用母函数来做了
//思想是相同的
#include<iostream>
using namespace std;
int c1[10005];
int c2[10005];
int n,sum,res;
int weight[105];
int main(){
while(scanf("%d",&n)!=EOF){
res=sum=0;
for(int i=0;i<n;i++){
scanf("%d",&weight[i]);
sum+=weight[i];
weight[n+i]=-weight[i];
}
memset(c1,0,sizeof(c1));
memset(c2,0,sizeof(c2));
for(int i=0;i<=weight[0];i+=weight[0])
c1[i]=1;
for(int i=1;i<2*n;i++){
for(int j=0;j<10005;j++){
if(i<=n-1){
for(int k=0;k<=weight[i];k+=weight[i]){
c2[j+k]+=c1[j];
}
}else{
for(int k=weight[i];k<=0;k+=-weight[i]){
if(j+k>=0){
c2[j+k]+=c1[j];
}
}
}
}
for(int j=0;j<10005;j++){
c1[j]=c2[j];
c2[j]=0;
}
}
//==================================output
for(int i=0;i<=sum;i++){
if(c1[i]==0){
res++;
}
}
//=====================================
bool flag=false;
printf("%d\n",res);
if(res!=0){
for(int i=0;i<=sum;i++){
if(c1[i]==0&&flag==false){
printf("%d",i);
flag=true;
}
else if(c1[i]==0&&flag){
printf(" %d",i);
}
}
printf("\n");
}
}
return 0;
}