def valid(neighbor, rows, columns):
    """Find out if neighbor cell is valid

    Args:
        neighbor (List of integers): Neighboring cell position
        rows (int): Number of rows on the board
        columns (int): Number of columns on the board

    Returns:
        [boolean]: True if valid, False otherwise
    """
    if neighbor[0] < 0 or neighbor[1] < 0:
        return False
    if neighbor[0] >= rows or neighbor[1] >= columns:
        return False
    return True