//In the name of GOD
//#pragma GCC optimize("O2")
#include<bits/stdc++.h>
#define md ((s + e) / 2)
#define dm ((s + e) / 2 + 1)
using namespace std;
typedef long long ll;
const ll MXN = 500 + 10;
const ll MXV = 25e4 + 10;
ll n, sum;
ll A[MXN], ANS[MXV];
bitset<MXV> inp;
void Upd(bitset<MXV> &bs, ll w){
bs |= (bs << w);
}
void solve(ll s, ll e, const bitset<MXV> &old){
if(s == e){
sum -= A[s];
//cout << "expect " << s << " : \n";
for(int w = (sum + 1) / 2; w <= sum; w ++){
if(old[w]){
//cout << w << ' ';
ANS[w - (sum - w)] ++;
}
}
//cout << '\n';
sum += A[s];
return;
}
bitset<MXV> nw = old;
for(int i = dm; i <= e; i ++) Upd(nw, A[i]);
solve(s, md, nw);
nw = old;
for(int i = s; i <= md; i ++) Upd(nw, A[i]);
solve(dm, e, nw);
}
int main(){
ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
cin >> n;
for(int i = 1; i <= n; i ++) cin >> A[i], sum += A[i];
inp[0] = 1;
for(int i = 1; i <= n; i ++) Upd(inp, A[i]);
if(sum % 2 == 1 || inp[sum / 2] == 0){
cout << 0 << '\n';
return 0;
}
for(int i = 0; i < MXV; i ++) inp[i] = 0;
inp[0] = 1;
solve(1, n, inp);
ll ans = 0;
for(int i = 0; i < MXV; i ++) ans += (ANS[i] == n);
cout << ans << '\n';
for(int i = 0; i < MXV; i ++){
if(ANS[i] == n) cout << i << ' ';
}
cout << '\n';
return 0;
}
//! N.N
