#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  vector<int> x(3), y(3), ax(3), ay(3);
  for (int i = 0; i < (3); i++) cin >> x[i] >> y[i];
  ax = x;
  sort(ax.begin(), ax.end());
  ay = y;
  sort(ay.begin(), ay.end());
  int mx = ax[1], my = ay[1];
  vector<pair<int, int>> ans({{mx, my}});
  for (int i = 0; i < (3); i++) {
    if (x[i] < mx)
      for (int j = x[i]; j < mx; j++) ans.push_back({j, y[i]});
    else
      for (int j = mx + 1; j <= x[i]; j++) ans.push_back({j, y[i]});
    if (y[i] < my)
      for (int j = y[i]; j < my; j++) ans.push_back({mx, j});
    else
      for (int j = my + 1; j <= y[i]; j++) ans.push_back({mx, j});
  }
  cout << ans.size() << '\n';
  for (auto pp : ans) cout << pp.first << ' ' << pp.second << '\n';
}
