#include <bits/stdc++.h>
using namespace std;
int main() {
  cin.tie(0)->sync_with_stdio(0);
  cin.exceptions(ios::badbit | ios::failbit);
  array<array<int, 2>, 3> a;
  array<int, 3> x, y;
  for (auto i = 0; i < 3; ++i) {
    for (auto j = 0; j < 2; ++j) {
      cin >> a[i][j];
    }
    x[i] = a[i][0], y[i] = a[i][1];
  }
  sort(x.begin(), x.end()), sort(y.begin(), y.end());
  int mx = x[1], my = y[1];
  vector<array<int, 2>> res{{mx, my}};
  for (auto [x, y] : a) {
    while (x > mx) {
      res.push_back({x--, y});
    }
    while (x < mx) {
      res.push_back({x++, y});
    }
    while (y > my) {
      res.push_back({x, y--});
    }
    while (y < my) {
      res.push_back({x, y++});
    }
  }
  cout << (int)res.size() << "\n";
  for (auto [x, y] : res) {
    cout << x << " " << y << "\n";
  }
  return 0;
}
