#include <bits/stdc++.h>
using namespace std;
int f(char a, char b, char c, char d) {
  int count = 0;
  if (a == '#') count++;
  if (b == '#') count++;
  if (c == '#') count++;
  if (d == '#') count++;
  if (count == 3 || count == 4 || count == 0 || count == 1)
    return 1;
  else
    return 0;
}
int main() {
  char a[5][5];
  for (int i = 1; i <= 4; i++)
    for (int j = 1; j <= 4; j++) cin >> a[i][j];
  for (int i = 1; i <= 3; i++) {
    for (int j = 1; j <= 3; j++) {
      if (f(a[i][j], a[i + 1][j], a[i][j + 1], a[i + 1][j + 1])) {
        cout << "YES" << endl;
        return 0;
      }
    }
  }
  cout << "NO" << endl;
  return 0;
}
