docs: private final boolean cons(int i) {
  		switch (b[i]) {
  		case 'a':
  		case 'e':
  		case 'i':
  		case 'o':
  		case 'u':
  			return false;
  		case 'y':
  			return (i == k0) ? true : !cons(i - 1);
  		default:
  			return true;
  		}
  	}