#include <bits/stdc++.h>
using namespace std;
void solve() {
  vector<pair<int, int>> v;
  for (int i = 0; i < 3; i++) {
    int x, y;
    cin >> x >> y;
    v.emplace_back(x, y);
  }
  int a[] = {v[0].first, v[1].first, v[2].first};
  int b[] = {v[0].second, v[1].second, v[2].second};
  sort(a, a + 3);
  sort(b, b + 3);
  int mx = a[1];
  int my = b[1];
  set<pair<int, int>> s;
  for (auto e : v) {
    int dx = e.first - mx;
    if (dx >= 0) {
      for (int i = e.first; i >= mx; i--) {
        s.insert({i, e.second});
        e.first = mx;
      }
    } else {
      for (int i = e.first; i <= mx; i++) {
        s.insert({i, e.second});
        e.first = mx;
      }
    }
    int dy = e.second - my;
    if (dy >= 0) {
      for (int i = e.second; i >= my; i--) {
        s.insert({mx, i});
      }
    } else {
      for (int i = e.second; i <= my; i++) {
        s.insert({mx, i});
      }
    }
  }
  cout << s.size() << "\n";
  for (auto e : s) cout << e.first << " " << e.second << "\n";
  cout << "\n";
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int t = 1;
  while (t--) solve();
}
