/// vonat1us
#pragma GCC optimize("O3")
//#pragma comment(linker, "/STACK:36777216")
#include<bits/stdc++.h>
#define x first
#define y second
#define pb push_back
#define sz(x) (int) x.size()
#define all(z) (z).begin(), (z).end()
using namespace std;
using ll = long long;
using pii = pair<int, int>;
const int MOD = 1e9 + 7;
const int INF = 1e9 + 1e2;
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
void fin() {
#ifdef AM
freopen(".in", "r", stdin);
#endif
}
const bool flag = 0;
const int N = 1e5+10;
const int B = 1e5+3e4;
bitset<B> dp;
int cnt[B];
void ma1n() {
int n;
cin >> n;
vector<int> a(n);
int s = 0;
for (int& x : a) {
cin >> x, s += x;
}
if (s&1) cout << 0, exit(0);
for (int i = -1; i < n; ++i) {
dp.reset();
dp.set(0, 1);
for (int j = 0; j < n; ++j) {
if (i == j) continue;
dp |= dp<<a[j];
}
if (i == -1) {
if (!dp[s/2]) {
cout << 0, exit(0);
}
continue;
}
for (int b = 0; b <= s/2; ++b) {
if (dp[b]) {
int balance = s-a[i]-b-b;
if (balance > 0) {
cnt[balance]++;
}
}
}
}
vector<int> ans;
for (int i = 0; i <= s; ++i) {
if (cnt[i] == n) {
ans.pb(i);
}
}
cout << sz(ans) << "\n";
for (int x : ans) cout << x << " ";
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(nullptr), fin();
int ts = 1;
if (flag) {
cin >> ts;
}
while (ts--) {
ma1n();
}
return 0;
}
