#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  pair<int, int> arr[3];
  for (int i = 0; i < 3; ++i) cin >> arr[i].first >> arr[i].second;
  set<pair<int, int>> ans;
  sort(arr, arr + 3);
  for (int i = arr[0].first; i <= arr[1].first; ++i)
    ans.insert({i, arr[0].second});
  for (int i = arr[1].first; i <= arr[2].first; ++i)
    ans.insert({i, arr[2].second});
  for (int i = arr[1].second; i <= arr[0].second || i <= arr[2].second; ++i)
    ans.insert({arr[1].first, i});
  for (int i = arr[1].second; i >= arr[0].second || i >= arr[2].second; --i)
    ans.insert({arr[1].first, i});
  cout << (int)ans.size() << '\n';
  for (auto i = ans.begin(); i != ans.end(); ++i)
    cout << (*i).first << ' ' << (*i).second << '\n';
  return 0;
}
