import re
from html import escape, unescape

BOLD_TAGS = ("<b>", "</b>")
TAG_RE = re.compile(r"(</?b>)")


def to_matrix(text: str) -> tuple[str, str]:
    plain, formatted = [], []
    for part in TAG_RE.split(text):
        if part in BOLD_TAGS:
            formatted.append(part)
            continue
        raw = unescape(part)
        plain.append(raw)
        formatted.append(escape(raw, quote=False).replace("\n", "<br>"))
    return "".join(plain), "".join(formatted)