#include <bits/stdc++.h>
int main() {
  int f = 0, i, j, cnt;
  char a[4][5];
  for (i = 0; i < 4; i++) scanf("%s", a[i]);
  for (i = 0; i < 3; i++) {
    cnt = 0;
    for (j = 0; j < 3; j++) {
      if (a[i][j] == '.') cnt++;
      if (a[i + 1][j] == '.') cnt++;
      if (a[i][j + 1] == '.') cnt++;
      if (a[i + 1][j + 1] == '.') cnt++;
      if (cnt != 2) {
        f = 1;
        break;
      } else
        cnt = 0;
    }
    if (f) break;
  }
  if (f == 0)
    printf("NO\n");
  else if (f == 1)
    printf("YES\n");
  return 0;
}
