#include <bits/stdc++.h>
using namespace std;
void __print(int x) { cerr << x; }
void __print(long x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(unsigned x) { cerr << x; }
void __print(unsigned long x) { cerr << x; }
void __print(unsigned long long x) { cerr << x; }
void __print(float x) { cerr << x; }
void __print(double x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }
template <typename T, typename V>
void __print(const pair<T, V> &x) {
  cerr << '{';
  __print(x.first);
  cerr << ',';
  __print(x.second);
  cerr << '}';
}
template <typename T>
void __print(const T &x) {
  int f = 0;
  cerr << '{';
  for (auto &i : x) cerr << (f++ ? "," : ""), __print(i);
  cerr << "}";
}
void _print() { cerr << "]\n"; }
template <typename T, typename... V>
void _print(T t, V... v) {
  __print(t);
  if (sizeof...(v)) cerr << ", ";
  _print(v...);
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  vector<pair<long long, long long> > v;
  long long x, y;
  for (long long i = 0; i < 3; i++) {
    cin >> x >> y;
    v.push_back(make_pair(x, y));
  }
  sort(v.begin(), v.end());
  long long mx_y = max(v[0].second, max(v[1].second, v[2].second));
  long long mn_y = min(v[0].second, min(v[1].second, v[2].second));
  vector<pair<long long, long long> > ans;
  for (long long i = mn_y; i <= mx_y; i++)
    ans.push_back(make_pair(v[1].first, i));
  for (long long i = (v[1].first - 1); i >= v[0].first; i--) {
    ans.push_back(make_pair(i, v[0].second));
  }
  for (long long i = v[1].first + 1; i <= v[2].first; i++) {
    ans.push_back(make_pair(i, v[2].second));
  }
  cout << ans.size() << endl;
  for (auto x : ans) cout << x.first << " " << x.second << endl;
}
