#include <bits/stdc++.h>
using namespace std;
long long ans = 1e10, aa, bb;
vector<pair<long long, long long> > v(3);
set<pair<long long, long long> > s;
void f(int x, int y) {
  long long dist = 0;
  for (long long i = 0; i < 3; i++)
    dist += abs(v[i].first - x) + abs(v[i].second - y) + 1;
  if (dist < ans) {
    ans = dist;
    aa = x, bb = y;
  }
}
void f1(pair<long long, long long> a) {
  for (long long i = min(a.first, aa); i < max(a.first, aa) + 1; i++)
    s.insert({i, (a.first <= aa) ? a.second : bb});
  for (long long i = min(a.second, bb); i < max(a.second, bb) + 1; i++)
    s.insert({max(a.first, aa), i});
}
void solve() {
  for (long long i = 0; i < 3; i++) cin >> v[i].first >> v[i].second;
  for (long long i = 0; i < 1001; i++)
    for (long long j = 0; j < 1001; j++) f(i, j);
  for (long long i = 0; i < 3; i++) f1(v[i]);
  cout << s.size() << "\n";
  for (auto j : s) cout << j.first << " " << j.second << "\n";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  for (long long i = 0; i < t; i++) solve();
  return 0;
}
