#include <bits/stdc++.h>
using namespace std;
int main() {
  vector<string> V;
  for (int i = 0; i < 4; ++i) {
    string s;
    cin >> s;
    V.push_back(s);
  }
  bool pos = false;
  for (int r = 0; r < 3; ++r) {
    for (int c = 0; c < 3; ++c) {
      int dots = 0, nums = 0;
      dots += (V[r][c] == '.');
      nums += (V[r][c] != '.');
      dots += (V[r][c + 1] == '.');
      nums += (V[r][c + 1] != '.');
      dots += (V[r + 1][c] == '.');
      nums += (V[r + 1][c] != '.');
      dots += (V[r + 1][c + 1] == '.');
      nums += (V[r + 1][c + 1] != '.');
      if (dots >= 3 || nums >= 3) pos = true;
    }
  }
  cout << (pos ? "YES" : "NO");
  return 0;
}
