import re


def parse(markdown):
    result = ''
    for line in markdown.splitlines():

        line = re.sub(r'__(.*)__', r'<strong>\1</strong>', line)
        line = re.sub(r'_(.*)_', r'<em>\1</em>', line)

        match = re.match(r'^(#{1,6}) (.*)', line)
        if match:
            level = len(match.group(1))
            result += f'<h{level}>{match.group(2)}</h{level}>'
            continue

        match = re.match(r'\* (.*)', line)
        if match:

            if result.endswith('</ul>'):
                result = result[:-5]
            else:
                result += '<ul>'

            result += '<li>' + match.group(1) + '</li></ul>'
            continue

        result += '<p>' + line + '</p>'

    return result