#include <bits/stdc++.h>
using namespace std;
vector<pair<int, int> > ans;
pair<int, int> ipt[3];
int x, y;
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  for (long long i = (0); i < (3); ++i) {
    cin >> x >> y;
    ipt[i] = make_pair(x, y);
  }
  sort(ipt, ipt + 3);
  for (long long i = (ipt[0].first); i < (ipt[1].first); ++i) {
    ans.push_back(make_pair(i, ipt[0].second));
  }
  for (long long i = (ipt[1].first + 1); i < (ipt[2].first + 1); ++i) {
    ans.push_back(make_pair(i, ipt[2].second));
  }
  int yy[3];
  for (long long i = (0); i < (3); ++i) yy[i] = ipt[i].second;
  sort(yy, yy + 3);
  for (long long j = (yy[0]); j < (yy[2] + 1); ++j) {
    ans.push_back(make_pair(ipt[1].first, j));
  }
  cout << ans.size() << endl;
  for (const auto &ele : ans) {
    cout << ele.first << ' ' << ele.second << endl;
  }
  return 0;
}
