#include <bits/stdc++.h>
using namespace std;
int x, y;
pair<int, int> p[3];
vector<pair<int, int> > Ans;
int main(void) {
  int mxX = 0, miX = 1e9, mxY = 0, miY = 1e9;
  for (int i = 0; i < 3; i++) {
    scanf("%d%d", &x, &y);
    mxX = max(mxX, x);
    miX = min(miX, x);
    mxY = max(mxY, y);
    miY = min(miY, y);
    p[i] = {x, y};
  }
  sort(p, p + 3);
  for (int i = miY; i <= mxY; i++) {
    Ans.emplace_back(p[1].first, i);
  }
  for (int i = miX; i < p[1].first; i++) {
    Ans.emplace_back(i, p[0].second);
  }
  for (int i = p[1].first + 1; i <= mxX; i++) {
    Ans.emplace_back(i, p[2].second);
  }
  printf("%d\n", Ans.size());
  for (int i = 0; i < Ans.size(); i++) {
    cout << Ans[i].first << " " << Ans[i].second << endl;
  }
}
