#include <bits/stdc++.h>
using namespace std;
const int MOD = 1000000007;
long double PI = 4 * atan(1);
pair<int, int> p[3];
set<pair<int, int> > second;
bool cmp(pair<int, int> p1, pair<int, int> p2) { return p1.second > p2.second; }
int main() {
  ios::sync_with_stdio(0), cin.tie(0);
  for (int i = 0; i < 3; i++) {
    cin >> p[i].first >> p[i].second;
    second.insert(p[i]);
  }
  sort(p, p + 3, cmp);
  while (p[2].second != p[1].second) {
    p[2].second++;
    second.insert(p[2]);
  }
  sort(p, p + 3, cmp);
  while (p[0].first != p[2].first) {
    if (p[0].first > p[2].first)
      p[2].first++;
    else
      p[2].first--;
    second.insert(p[2]);
  }
  while (p[0].first != p[1].first) {
    if (p[0].first > p[1].first)
      p[1].first++;
    else
      p[1].first--;
    second.insert(p[1]);
  }
  p[1] = p[2];
  while (p[2].second != p[0].second) {
    p[2].second++;
    second.insert(p[2]);
  }
  cout << second.size() << "\n";
  for (pair<int, int> p1 : second) {
    cout << p1.first << " " << p1.second << "\n";
  }
  return 0;
}
