def zero_year_special_case(from_date, to_date, start, end):
    if start == 'pos' and end == 'pos':
        if from_date.startswith('0000') and not to_date.startswith('0000'):
            return True
        if not from_date.startswith('0000') and to_date.startswith('0000'):
            return False
        if from_date.startswith('0000') and to_date.startswith('0000'):
            if len(from_date) == 4:
                fm, fd = 1, 1
            elif len(from_date) == 7:
                fm, fd = int(from_date[5:7]), 1
            elif len(from_date) == 10:
                fm, fd = int(from_date[5:7]), int(from_date[8:10])
            if len(to_date) == 4:
                tm, td = 1, 1
            elif len(to_date) == 7:
                tm, td = int(to_date[5:7]), 1
            elif len(to_date) == 10:
                tm, td = int(to_date[5:7]), int(to_date[8:10])
            if from_date == to_date:
                return True
            if fm <= tm:
                if fd <= td:
                    return True
                else:
                    return False
            else:
                return False
    elif start == 'neg' and end == 'neg':
        return False
    elif start == 'neg' and end == 'pos':
        if from_date.startswith("0000"):
            return False
        else:
            return True