#include <bits/stdc++.h>
using namespace std;
int main() {
  int b[3][2];
  int count = 0;
  for (int i = 0; i < 3; ++i) cin >> b[i][0] >> b[i][1];
  for (int i = 0; i < 3; ++i)
    for (int j = i + 1; j < 3; ++j) {
      if (b[j][1] < b[i][1]) {
        int t, k;
        t = b[j][1];
        b[j][1] = b[i][1];
        b[i][1] = t;
        k = b[j][0];
        b[j][0] = b[i][0];
        b[i][0] = k;
      }
    }
  int des1 = min(b[1][0], b[0][0]);
  int des2 = max(b[1][0], b[0][0]);
  for (int k = b[2][1]; k >= b[1][1]; --k) count++;
  if (min(b[1][0], b[0][0]) <= b[2][0] && max(b[1][0], b[0][0]) >= b[2][0]) {
    for (int k = b[2][0] - 1; k >= des1; --k) count++;
    for (int k = b[2][0] + 1; k <= des2; ++k) count++;
  } else {
    if (des2 < b[2][0])
      for (int k = b[2][0] - 1; k >= des1; --k) count++;
    else {
      for (int k = b[2][0] + 1; k <= des2; ++k) count++;
    }
  }
  for (int k = b[1][1] - 1; k >= b[0][1]; --k) count++;
  cout << count << "\n";
  for (int k = b[2][1]; k >= b[1][1]; --k) cout << b[2][0] << " " << k << "\n";
  if (min(b[1][0], b[0][0]) <= b[2][0] && max(b[1][0], b[0][0]) >= b[2][0]) {
    for (int k = b[2][0] - 1; k >= des1; --k)
      cout << k << " " << b[1][1] << "\n";
    for (int k = b[2][0] + 1; k <= des2; ++k)
      cout << k << " " << b[1][1] << "\n";
  } else {
    if (des2 < b[2][0])
      for (int k = b[2][0] - 1; k >= des1; --k)
        cout << k << " " << b[1][1] << "\n";
    else {
      for (int k = b[2][0] + 1; k <= des2; ++k)
        cout << k << " " << b[1][1] << "\n";
    }
  }
  for (int k = b[1][1] - 1; k >= b[0][1]; --k)
    cout << b[0][0] << " " << k << "\n";
}
