#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
#define MASK(i) (1ULL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
#define ALL(v) (v).begin(), (v).end()
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
ll gcd(ll a, ll b){return __gcd(abs(a), abs(b));}
ll lcm(ll a, ll b){return abs(a) / gcd(a, b) * abs(b);}
ll LASTBIT(ll mask){return (mask) & (-mask);}
int pop_cnt(ull mask){return __builtin_popcountll(mask);}
int ctz(ull mask){return __builtin_ctzll(mask);}
int logOf(ull mask){return 63 - __builtin_clzll(mask);}
mt19937_64 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rngesus(ll l, ll r){return l + (ull) rng() % (r - l + 1);}
template <class T1, class T2>
bool maximize(T1 &a, T2 b){
if (a < b) {a = b; return true;}
return false;
}
template <class T1, class T2>
bool minimize(T1 &a, T2 b){
if (a > b) {a = b; return true;}
return false;
}
template <class T>
void printArr(T container, string separator = " ", string finish = "\n", ostream &out = cout){
for(auto item: container) out << item << separator;
out << finish;
}
template <class T>
void remove_dup(vector<T> &a){
sort(ALL(a));
a.resize(unique(ALL(a)) - a.begin());
}
void solve(){
int n; cin >> n;
vector<pair<ll, ll>> a(n);
for(int i = 0; i < n; ++i) cin >> a[i].first >> a[i].second;
sort(ALL(a));
ll area = 0;
for(auto i: a) area += 1LL * i.first * i.second;
vector<ll> candidate;
ll ma = 0;
for(pair<int, int> i: a) maximize(ma, i.second);
if (area % ma == 0) candidate.push_back(ma);
if (ma == 1){
candidate.push_back(a.back().first);
}
else{
for(pair<int, int> i: a){
if (i.first <= ma) continue;
if (area % i.first == 0) candidate.push_back(i.first);
}
}
for(ll &i: candidate) {
minimize(i, area / i);
}
remove_dup(candidate);
vector<ll> ans;
for(ll i: candidate){
ll goy = i;
ll j = area / i;
multiset<pair<int, int>> S1, S2;
for(pair<int, int> i: a){
S1.insert(i);
S2.insert(make_pair(i.second, i.first));
}
bool check = true;
for(int it = 1; it <= n; ++it){
if (i < j) swap(i, j);
pair<int, int> ma = {-1, -1};
for(int x = 0; x <= 1; ++x){
for(int y = 0; y<= 1; ++y){
auto it = S1.lower_bound(make_pair(i+1, -1));
if (it != S1.begin()) {
it--;
if ((*it).first == i){
pair<int, int> cur = (*it);
maximize(ma, cur);
}
}
swap(S1, S2);
}
swap(i, j);
}
if (ma.first == -1){
check = false;
break;
}
bool cur_found = false;
for(int x = 0; x <= 1; ++x){
for(int y = 0; y<= 1; ++y){
auto it = S1.lower_bound(make_pair(i+1, -1));
if (it != S1.begin()){
it--;
if ((*it).first == i){
pair<int, int> cur = (*it);
if (cur == ma){
j -= cur.second;
S1.erase(S1.find(cur));
swap(cur.first, cur.second);
S2.erase(S2.find(cur));
cur_found = true;
break;
}
}
}
swap(S1, S2);
}
if (cur_found) break;
swap(i, j);
}
}
if (check) ans.push_back(goy);
}
cout << ans.size() << "\n";
for(int i: ans) cout << i << "\n";
}
int main(void){
ios::sync_with_stdio(0);cin.tie(0); cout.tie(0);
clock_t start = clock();
solve();
cerr << "Time elapsed: " << clock() - start << "ms!\n";
return 0;
}
