#include <bits/stdc++.h>
using namespace std;
int main() {
  vector<pair<int, int> > pts, ans;
  for (int i = 0; i < 3; i++) {
    int x, y;
    cin >> x >> y;
    pts.push_back({x, y});
  }
  sort(pts.begin(), pts.end());
  for (int x = pts[0].first; x < pts[1].first; x++)
    ans.push_back({x, pts[0].second});
  for (int x = pts[1].first + 1; x <= pts[2].first; x++)
    ans.push_back({x, pts[2].second});
  int ymax = max({pts[0].second, pts[1].second, pts[2].second}),
      ymin = min({pts[0].second, pts[1].second, pts[2].second});
  for (int y = ymax; y >= ymin; y--) ans.push_back({pts[1].first, y});
  cout << ans.size() << endl;
  for (pair<int, int> p : ans) cout << p.first << " " << p.second << endl;
}
