#pragma GCC optimize("O3")
#pragma GCC target("popcnt")
#include <bits/stdc++.h>
using namespace std;
#define IShowSpeed ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define popcnt __builtin_popcount
#define all(a) a.begin(),a.end()
#define pii pair<int,int>
#define mii map<int,int>
#define pll pair<ll,ll>
#define mll map<ll,ll>
#define pb push_back
#define vt vector
#define endl '\n'
#define X first
#define Y second
typedef long double ld;
typedef long long ll;
const ll dx[4]={1,-1,0,0},dy[4]={0,0,1,-1},N=1e6;
const ll mod=1e9+7,inf=1e18;
int dp[N];
void solve(){
int n;
cin>>n;
int a[n+2],sum=0;
for(int i=1; i<=n; ++i) {cin>>a[i];sum+=a[i];}
dp[0]=1;
mii used;
for(int j=1; j<=n; ++j) for(int i=sum; i>=a[j]; --i) dp[i]+=dp[i-a[j]];
if(!dp[sum/2] || sum%2){
cout<<0<<endl;
return;
}
vt<int>res;
for(int i=1; i<=n; ++i){
for(int j=a[i]; j<=sum; ++j) dp[j]-=dp[j-a[i]];
for(int nd=1; nd<=sum; ++nd){
int h=sum-a[i];
h+=nd;
if(h%2 || !dp[h/2]) continue;
used[nd]++;
if(used[nd]==n)res.pb(nd);
}
for(int j=sum; j>=a[i]; --j) dp[j]+=dp[j-a[i]];
}
cout<<res.size()<<endl;
for(int x:res)cout<<x<<' ';
}
int main() {
IShowSpeed;
int tt=1;
//cin>>tt;
while(tt--) solve();
}
