#include <bits/stdc++.h>
const long long mod = 998244353;
using namespace std;
pair<long long, long long> v[10];
vector<pair<long long, long long> > ans;
long long us[1111][1111];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> v[1].first >> v[1].second;
  cin >> v[2].first >> v[2].second;
  cin >> v[3].first >> v[3].second;
  sort(v + 1, v + 4);
  long long x = v[2].first;
  for (long long i = min(v[1].second, min(v[2].second, v[3].second));
       i <= max(v[1].second, max(v[2].second, v[3].second)); i++) {
    us[x][i] = 1;
    ans.push_back({x, i});
  }
  for (long long i = v[1].first; i <= v[2].first; i++) {
    if (us[i][v[1].second] == 0) {
      us[i][v[1].second] = 0;
      ans.push_back({i, v[1].second});
    }
  }
  for (long long i = v[2].first; i <= v[3].first; i++) {
    if (us[i][v[3].second] == 0) {
      us[i][v[3].second] = 0;
      ans.push_back({i, v[3].second});
    }
  }
  cout << ans.size() << endl;
  for (long long i = 0; i < ans.size(); i++) {
    cout << ans[i].first << " " << ans[i].second << endl;
  }
  return 0;
}
