#include <bits/stdc++.h>
using namespace std;
int main() {
  int i, j, b, w;
  bool ans = false;
  char m[4][4];
  for (int i = 0; i < 4; ++i) {
    for (int j = 0; j < 4; ++j) {
      cin >> m[i][j];
    }
  }
  for (int i = 0; i < 3; ++i) {
    for (int j = 0; j < 3; ++j) {
      b = 0;
      w = 0;
      if (m[i][j] == '#')
        b++;
      else
        w++;
      if (m[i][j + 1] == '#')
        b++;
      else
        w++;
      if (m[i + 1][j] == '#')
        b++;
      else
        w++;
      if (m[i + 1][j + 1] == '#')
        b++;
      else
        w++;
      if (b >= 3 || w >= 3) {
        ans = true;
        i = 4;
        break;
      }
    }
  }
  if (ans)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
