#include <bits/stdc++.h>
const long long inf = std::numeric_limits<long long>::max();
const int infint = std::numeric_limits<int>::max();
const long long mod = 1e9 + 7;
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
vector<pair<int, int> > ans, v;
map<pair<int, int>, bool> mp;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  for (int i = 0; i < 3; i++) {
    int x, y;
    cin >> x >> y;
    v.push_back({x, y});
  }
  sort(v.begin(), v.end());
  int vas = 1;
  for (int i = 0; i < 3; i++) {
    if (vas == i) continue;
    int mn, mx;
    mn = min(v[vas].first, v[i].first);
    mx = max(v[vas].first, v[i].first);
    for (int j = mn; j < mx + 1; j++) {
      if (mp[{j, v[i].second}]) continue;
      mp[{j, v[i].second}] = true;
      ans.push_back({j, v[i].second});
    }
    mn = min(v[vas].second, v[i].second);
    mx = max(v[vas].second, v[i].second);
    for (int j = mn; j < mx + 1; j++) {
      if (mp[{v[vas].first, j}]) continue;
      mp[{v[vas].first, j}] = true;
      ans.push_back({v[vas].first, j});
    }
  }
  cout << ans.size() << '\n';
  for (auto i : ans) cout << i.first << ' ' << i.second << '\n';
  return 0;
}
