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# /// script
# requires-python = ">=3.9"
# dependencies = [
#     "datasets>=2.0.0",
#     "underthesea>=6.8.0",
# ]
# ///
"""
Fetch sentences for word segmentation dataset (100K total).

Fetches 20,000 sentences per domain from 4 HuggingFace datasets:
  - Legal:       undertheseanlp/UTS_VLC     → ws_sentences_vlc.txt
  - News:        undertheseanlp/UVN-1       → ws_sentences_uvn.txt
  - Wikipedia:   undertheseanlp/UVW-2026    → ws_sentences_uvw.txt
  - Fiction:     undertheseanlp/UVB-v0.1    → ws_sentences_uvb_f.txt
  - Non-fiction: undertheseanlp/UVB-v0.1    → ws_sentences_uvb_n.txt

Output format: idx\tsentence (one sentence per line)
"""

import re
from os.path import dirname, join

from datasets import load_dataset
from underthesea import lang_detect, sent_tokenize, text_normalize


TARGET_PER_DOMAIN = 20000

# Vietnamese toned vowels — each syllable has at most one tone mark.
# A whitespace-delimited token with 2+ toned vowels is glued text.
TONED_VOWELS = set(
    'áàảãạắằẳẵặấầẩẫậéèẻẽẹếềểễệíìỉĩịóòỏõọốồổỗộớờởỡợúùủũụứừửữựýỳỷỹỵ'
    'ÁÀẢÃẠẮẰẲẴẶẤẦẨẪẬÉÈẺẼẸẾỀỂỄỆÍÌỈĨỊÓÒỎÕỌỐỒỔỖỘỚỜỞỠỢÚÙỦŨỤỨỪỬỮỰÝỲỶỸỴ'
)

# All Vietnamese diacritical characters (toned vowels + base vowels ă, â, ê, ô, ơ, ư, đ)
VIET_DIACRITICS = TONED_VOWELS | set('ăâêôơưđĂÂÊÔƠƯĐ')

# Characters unique to Vietnamese (not in French/Portuguese/other Latin scripts)
# ă/ơ/ư and their toned variants distinguish Vietnamese from French (which shares â, ê, ô, é, è, à)
VIET_ONLY_CHARS = set('ăắằẳẵặơớờởỡợưứừửữựđ'
                      'ĂẮẰẲẴẶƠỚỜỞỠỢƯỨỪỬỮỰĐ')


# ============================================================================
# Shared text cleaning
# ============================================================================

def clean_text(text):
    """Remove markdown formatting and clean text."""
    text = text_normalize(text)
    text = re.sub(r'^#+\s+', '', text, flags=re.MULTILINE)
    text = re.sub(r'\*+', '', text)
    text = re.sub(r'^-+$', '', text, flags=re.MULTILINE)
    text = re.sub(r'\[([^\]]+)\]\([^)]+\)', r'\1', text)
    text = re.sub(r'\n{2,}', '\n', text)
    lines = [line.strip() for line in text.split('\n')]
    text = '\n'.join(lines)
    return text


def safe_sent_tokenize(text):
    """Sentence tokenize with fix for numbers split across sentence boundaries.

    underthesea's sent_tokenize splits "2.000" into ["...hơn 2.", "000 học sinh..."].
    This merges consecutive sentences where the split occurred inside a number.
    """
    raw_sents = sent_tokenize(text)
    if not raw_sents:
        return raw_sents
    merged = [raw_sents[0]]
    for sent in raw_sents[1:]:
        prev = merged[-1]
        # Previous ends with digit(s) + period, current starts with digit(s)
        if re.search(r'\d\s*\.\s*$', prev) and re.match(r'\d', sent):
            merged[-1] = prev + sent
        else:
            merged.append(sent)
    return merged


def sentence_score(sent):
    """Score a sentence's quality on a (0, 1) scale.

    Combines 6 sub-scores:
      1. Length score     — Gaussian around ideal range [60, 200] chars
      2. Word count score — Gaussian around ideal range [8, 35] words
      3. Vietnamese density — ratio of Vietnamese diacritical chars to total letters
      4. Structure score  — proper start (uppercase/digit) + proper end (punctuation)
      5. Cleanliness score — absence of markup, unbalanced brackets, glued text
      6. Completeness score — balanced quotes, no trailing fragments

    Returns a float in (0, 1). Higher is better.
    """
    import math

    sent = sent.strip()
    if not sent:
        return 0.0

    # --- 1. Length score (0-1): Gaussian penalty outside [60, 200] ---
    char_len = len(sent)
    if 60 <= char_len <= 200:
        len_score = 1.0
    elif char_len < 60:
        len_score = math.exp(-0.5 * ((char_len - 60) / 30) ** 2)
    else:
        len_score = math.exp(-0.5 * ((char_len - 200) / 60) ** 2)

    # --- 2. Word count score (0-1): Gaussian penalty outside [8, 35] ---
    words = sent.split()
    wc = len(words)
    if 8 <= wc <= 35:
        wc_score = 1.0
    elif wc < 8:
        wc_score = math.exp(-0.5 * ((wc - 8) / 3) ** 2)
    else:
        wc_score = math.exp(-0.5 * ((wc - 35) / 10) ** 2)

    # --- 3. Vietnamese density (0-1): diacritical chars / total letters ---
    total_letters = sum(1 for c in sent if c.isalpha())
    viet_chars = sum(1 for c in sent if c in VIET_DIACRITICS)
    viet_score = min(viet_chars / max(total_letters, 1) * 5, 1.0)  # 20%+ diacritics → 1.0

    # --- 4. Structure score (0-1): start + end quality ---
    start_ok = 0.5 if (sent[0].isupper() or sent[0].isdigit()) else 0.0
    end_ok = 0.5 if sent[-1] in '.!?…"»"\'):' else 0.0
    struct_score = start_ok + end_ok

    # --- 5. Cleanliness score (0-1): penalty for noise signals ---
    clean_score = 1.0
    # Markup characters
    if re.search(r'[{}<>|]', sent):
        clean_score -= 0.3
    if re.search(r'\w+=\w+', sent):
        clean_score -= 0.2
    # Unbalanced brackets
    for o, c in [('(', ')'), ('[', ']')]:
        if sent.count(o) != sent.count(c):
            clean_score -= 0.2
            break
    # Glued text
    for token in words:
        tone_count = sum(1 for ch in token if ch in TONED_VOWELS)
        if tone_count >= 2:
            clean_score -= 0.3
            break
        if tone_count >= 1 and re.search(r'\d[a-zA-ZĐđÀ-ỹ]', token):
            clean_score -= 0.3
            break
    # File extensions
    if re.search(r'\.(jpg|jpeg|png|gif|svg|webp)\b', sent, re.IGNORECASE):
        clean_score -= 0.2
    # Excessive uppercase
    if sum(1 for c in sent if c.isupper()) > len(sent) * 0.5:
        clean_score -= 0.2
    clean_score = max(clean_score, 0.0)

    # --- 6. Completeness score (0-1): balanced quotes, no fragments ---
    comp_score = 1.0
    # Unbalanced quotes
    double_quotes = sent.count('"') + sent.count('\u201c') + sent.count('\u201d')
    if double_quotes % 2 != 0:
        comp_score -= 0.2
    # Excessive digit ratio
    digit_ratio = sum(1 for c in sent if c.isdigit()) / max(len(sent), 1)
    if digit_ratio > 0.3:
        comp_score -= 0.3
    elif digit_ratio > 0.2:
        comp_score -= 0.1
    comp_score = max(comp_score, 0.0)

    # --- Weighted combination ---
    # Vietnamese density is a multiplier (gate): non-Vietnamese → near 0
    base_score = (
        0.20 * len_score
        + 0.15 * wc_score
        + 0.20 * struct_score
        + 0.30 * clean_score
        + 0.15 * comp_score
    )
    score = base_score * viet_score
    return round(max(0.01, min(score, 0.99)), 4)


def base_valid(sent):
    """Shared base validation: length, word count, structure, language, punctuation, markup."""
    sent = sent.strip()
    if not sent:
        return False, sent
    if len(sent) < 20 or len(sent) > 300:
        return False, sent
    # Minimum word count — ensures enough syntactic structure
    if len(sent.split()) < 4:
        return False, sent
    # Must start with uppercase letter or digit
    if not sent[0].isupper() and not sent[0].isdigit():
        return False, sent
    # Must end with proper punctuation (including : and ) for legal/academic)
    if sent[-1] not in '.!?…"»"\'):':
        return False, sent
    if not re.search(r'[àáảãạăắằẳẵặâấầẩẫậèéẻẽẹêếềểễệìíỉĩịòóỏõọôốồổỗộơớờởỡợùúủũụưứừửữựỳýỷỹỵđ]', sent, re.IGNORECASE):
        return False, sent
    if sum(1 for c in sent if c.isupper()) > len(sent) * 0.5:
        return False, sent
    # Markup characters — reject template/HTML remnants
    if re.search(r'[{}<>]', sent):
        return False, sent
    if '|' in sent:
        return False, sent
    # Template-like = (no spaces): reject "key=value" but allow "x = y"
    if re.search(r'\w+=\w+', sent):
        return False, sent
    # Unbalanced brackets — opening and closing counts must match
    for open_ch, close_ch in [('(', ')'), ('[', ']')]:
        if sent.count(open_ch) != sent.count(close_ch):
            return False, sent
    # File extension remnants (wiki image markup)
    if re.search(r'\.(jpg|jpeg|png|gif|svg|webp)\b', sent, re.IGNORECASE):
        return False, sent
    # Glued text — two syllables merged without space
    for token in sent.split():
        tone_count = sum(1 for c in token if c in TONED_VOWELS)
        # Vietnamese syllable has at most 1 tone mark; 2+ means glued (e.g., "lõmlà")
        if tone_count >= 2:
            return False, sent
        # Digit glued to Vietnamese text (e.g., "59Sẹo")
        if tone_count >= 1 and re.search(r'\d[a-zA-ZĐđÀ-ỹ]', token):
            return False, sent
    # Language detection with Vietnamese-only character fallback
    if lang_detect(sent) != "vi":
        # Fallback: accept only if sentence has Vietnamese-only chars (ă, ơ, ư, đ and variants)
        # French shares â, ê, ô, é, è, à with Vietnamese, so those are not sufficient
        vn_only_count = sum(1 for c in sent if c in VIET_ONLY_CHARS)
        if vn_only_count < 1:
            return False, sent
    return True, sent


# ============================================================================
# Domain-specific validators
# ============================================================================

def is_valid_legal(sent):
    """Validate sentence from legal domain (UTS_VLC)."""
    ok, sent = base_valid(sent)
    if not ok:
        return False, sent
    # Remove trailing list markers
    sent = re.sub(r'\n\d+\.$', '', sent)
    sent = re.sub(r'\n[a-z]\)$', '', sent)
    sent = sent.strip()
    if not sent:
        return False, sent
    # Skip legal structure headers
    if re.match(r'^(QUỐC HỘI|CỘNG HÒA|Độc lập|Phần thứ|Chương [IVX]+|MỤC \d+)', sent):
        return False, sent
    if re.match(r'^(Điều \d+|Khoản \d+|Mục \d+)', sent):
        return False, sent
    if sent.startswith(('English:', 'Số hiệu:', 'Ngày hiệu lực:', '---', '|')):
        return False, sent
    if re.search(r'\n\d+$', sent):
        return False, sent
    return True, sent


def is_valid_news(sent):
    """Validate sentence from news domain (UVN-1)."""
    ok, sent = base_valid(sent)
    if not ok:
        return False, sent
    # Skip bylines
    if re.match(r'^(Theo |PV |Nguồn:|Ảnh:|Video:|Bài:|Tin ảnh:)', sent):
        return False, sent
    # Skip photo captions
    if re.search(r'\(Ảnh:.*\)$', sent):
        return False, sent
    if re.search(r'\(Nguồn:.*\)$', sent):
        return False, sent
    # Skip date/time at start
    if re.match(r'^\d{1,2}/\d{1,2}/\d{4}', sent):
        return False, sent
    if re.match(r'^\d{1,2}:\d{2}', sent):
        return False, sent
    # Skip URLs
    if re.search(r'(http|www\.|\.com|\.vn)', sent, re.IGNORECASE):
        return False, sent
    # Skip tags/categories
    if re.match(r'^(Tags?:|Chuyên mục:|Từ khóa:)', sent, re.IGNORECASE):
        return False, sent
    # Skip data tables (>30% digits)
    if sum(1 for c in sent if c.isdigit()) > len(sent) * 0.3:
        return False, sent
    return True, sent


def is_valid_wiki(sent):
    """Validate sentence from Wikipedia domain (UVW-2026)."""
    ok, sent = base_valid(sent)
    if not ok:
        return False, sent
    # Skip stub markers
    if re.search(r'(bài sơ khai|sơ khai về|cần được mở rộng|Thể loại:)', sent):
        return False, sent
    # Skip category/list pages
    if re.match(r'^(Thể loại|Danh sách|Xem thêm|Tham khảo|Liên kết ngoài|Chú thích)', sent):
        return False, sent
    # Skip infobox remnants
    if sent.count('|') >= 2:
        return False, sent
    # Skip reference fragments
    if re.search(r'\[\d+\]', sent):
        return False, sent
    if re.search(r'\[cần', sent):
        return False, sent
    # Skip URLs
    if re.search(r'(http|www\.|\.com|\.org)', sent, re.IGNORECASE):
        return False, sent
    # Skip data tables
    if sum(1 for c in sent if c.isdigit()) > len(sent) * 0.3:
        return False, sent
    # Skip list items
    if re.match(r'^[\*\-•]\s', sent):
        return False, sent
    return True, sent


def is_valid_book(sent):
    """Validate sentence from book domain (UVB-v0.1) — stricter quality on top of base_valid."""
    ok, sent = base_valid(sent)
    if not ok:
        return False, sent
    # Stricter length
    if len(sent) < 30 or len(sent) > 250:
        return False, sent
    # Word count
    words = sent.split()
    if len(words) < 5 or len(words) > 40:
        return False, sent
    # Stricter uppercase threshold
    if sum(1 for c in sent if c.isupper()) > len(sent) * 0.3:
        return False, sent
    # Skip too many numbers
    if sum(1 for c in sent if c.isdigit()) > len(sent) * 0.15:
        return False, sent
    # Skip structure markers
    if re.match(r'^(Chương|Phần|Mục|Điều|\d+\.|\([a-z]\))', sent):
        return False, sent
    # Skip URLs/emails
    if re.search(r'(http|www\.|@|\.com|\.vn)', sent, re.IGNORECASE):
        return False, sent
    # Skip excessive punctuation
    punct_count = sum(1 for c in sent if c in '.,;:!?-\u2013\u2014()[]""\'\'\xab\xbb')
    if punct_count > len(words) * 1.5:
        return False, sent
    # Skip incomplete sentences (ellipsis in middle)
    if '...' in sent[:-5]:
        return False, sent
    # Skip dialogue-heavy
    quote_count = sent.count('"') + sent.count('\u201c') + sent.count('\u201d')
    if quote_count > 4:
        return False, sent
    return True, sent


# ============================================================================
# Book genre classification (from fetch_uvb_data.py)
# ============================================================================

FICTION_GENRES = {
    "Fiction", "Novels", "Romance", "Fantasy", "Science Fiction",
    "Mystery", "Thriller", "Horror", "Historical Fiction", "Literary Fiction",
    "Adventure", "Crime", "Suspense", "Drama", "Short Stories"
}

NON_FICTION_GENRES = {
    "Non Fiction", "Nonfiction", "History", "Biography", "Autobiography",
    "Self Help", "Psychology", "Philosophy", "Science", "Politics",
    "Economics", "Business", "Education", "Travel", "Memoir",
    "Essays", "Reference", "Health", "Religion", "Spirituality"
}


def classify_book(genres):
    """Classify book as fiction or non-fiction based on genres."""
    if not genres:
        return None
    genres_set = set(genres)
    is_fiction = bool(genres_set & FICTION_GENRES)
    is_non_fiction = bool(genres_set & NON_FICTION_GENRES)
    if is_fiction and not is_non_fiction:
        return "fiction"
    elif is_non_fiction and not is_fiction:
        return "non-fiction"
    elif is_fiction and is_non_fiction:
        fiction_count = len(genres_set & FICTION_GENRES)
        non_fiction_count = len(genres_set & NON_FICTION_GENRES)
        return "fiction" if fiction_count > non_fiction_count else "non-fiction"
    return None


# ============================================================================
# Sentence extraction helpers
# ============================================================================

def normalize_for_dedup(sent):
    """Normalize sentence for near-duplicate detection.

    Replaces all digit sequences with '#' so that sentences differing only
    in numbers (e.g., article numbers, amounts) are treated as duplicates.
    Also lowercases for case-insensitive matching.
    """
    return re.sub(r'\d+', '#', sent.lower())


MAX_PER_DOC = 500  # Cap sentences per document to ensure source diversity


def extract_sentences(docs, validator, target, label=""):
    """Extract validated, deduplicated sentences from documents via round-robin.

    Phase 1: Scan all documents, collect up to MAX_PER_DOC valid sentences each.
    Phase 2: Round-robin across documents to ensure even source representation.
    """
    # Phase 1: collect candidate sentences per document
    doc_pools = []  # list of [sentences]
    for idx, doc in enumerate(docs):
        content = doc["content"]
        content = clean_text(content)
        sents = []
        for sent in safe_sent_tokenize(content):
            sent = sent.strip()
            ok, cleaned = validator(sent)
            if ok:
                sents.append(cleaned)
            if len(sents) >= MAX_PER_DOC:
                break
        if sents:
            doc_pools.append(sents)
        if (idx + 1) % 200 == 0:
            print(f"  {label}: [{idx+1}] docs scanned, {len(doc_pools)} with valid sentences")
        # Stop scanning if we have enough candidates (3x target for safety)
        total_candidates = sum(len(s) for s in doc_pools)
        if total_candidates >= target * 3:
            print(f"  {label}: [{idx+1}] docs scanned, {len(doc_pools)} with candidates, {total_candidates:,} total")
            break

    if not doc_pools:
        return []

    total_candidates = sum(len(s) for s in doc_pools)
    print(f"  {label}: {len(doc_pools)} docs with candidates, {total_candidates:,} total candidate sentences")

    # Phase 2: round-robin selection with dedup
    sentences = []
    seen = set()
    seen_normalized = set()
    round_idx = 0

    while len(sentences) < target and doc_pools:
        made_progress = False
        for i in range(len(doc_pools)):
            sents = doc_pools[i]
            if round_idx >= len(sents):
                continue
            cleaned = sents[round_idx]
            if cleaned in seen:
                continue
            norm = normalize_for_dedup(cleaned)
            if norm in seen_normalized:
                continue
            seen.add(cleaned)
            seen_normalized.add(norm)
            sentences.append(cleaned)
            made_progress = True
            if len(sentences) >= target:
                break
        if not made_progress:
            break
        # Remove exhausted documents
        doc_pools = [s for s in doc_pools if round_idx + 1 < len(s)]
        round_idx += 1

    print(f"  {label}: {len(sentences):,} sentences from {round_idx} rounds")
    return sentences[:target]


MAX_PER_BOOK = 500  # Cap sentences per book to ensure source diversity


def extract_book_sentences(books, target, label=""):
    """Extract validated, deduplicated sentences from books via round-robin.

    Phase 1: Extract up to MAX_PER_BOOK valid sentences from each book.
    Phase 2: Round-robin across all books to ensure even representation.
    """
    # Phase 1: collect candidate sentences per book
    book_pools = []  # list of (title, [sentences])
    for i, book in enumerate(books):
        content = clean_text(book["content"])
        sents = []
        for sent in safe_sent_tokenize(content):
            ok, cleaned = is_valid_book(sent)
            if ok:
                sents.append(cleaned)
            if len(sents) >= MAX_PER_BOOK:
                break
        if sents:
            book_pools.append((book["title"], sents))
        if (i + 1) % 50 == 0:
            print(f"  {label}: [{i+1}/{len(books)}] books scanned, {len(book_pools)} with valid sentences")

    total_candidates = sum(len(s) for _, s in book_pools)
    print(f"  {label}: {len(book_pools)} books with candidates, {total_candidates:,} total candidate sentences")

    # Phase 2: round-robin selection with dedup
    sentences = []
    seen = set()
    seen_normalized = set()
    round_idx = 0
    books_contributed = set()

    while len(sentences) < target and book_pools:
        made_progress = False
        for i in range(len(book_pools)):
            title, sents = book_pools[i]
            if round_idx >= len(sents):
                continue
            cleaned = sents[round_idx]
            if cleaned in seen:
                continue
            norm = normalize_for_dedup(cleaned)
            if norm in seen_normalized:
                continue
            seen.add(cleaned)
            seen_normalized.add(norm)
            sentences.append(cleaned)
            books_contributed.add(title)
            made_progress = True
            if len(sentences) >= target:
                break
        if not made_progress:
            break
        # Remove exhausted books
        book_pools = [(t, s) for t, s in book_pools if round_idx + 1 < len(s)]
        round_idx += 1

    print(f"  {label}: {len(sentences):,} sentences from {len(books_contributed)} books ({round_idx} rounds)")
    return sentences[:target]


def save_sentences(sentences, filepath):
    """Save sentences to file in idx\\tsentence format."""
    with open(filepath, "w", encoding="utf-8") as f:
        for i, sent in enumerate(sentences, 1):
            f.write(f"{i}\t{sent}\n")
    print(f"  Saved {len(sentences)} sentences to {filepath}")


# ============================================================================
# Main
# ============================================================================

def main():
    base_dir = dirname(dirname(__file__))

    # --- Legal (UTS_VLC) ---
    print(f"\n[1/5] Fetching legal sentences (target: {TARGET_PER_DOMAIN})...")
    ds_vlc = load_dataset("undertheseanlp/UTS_VLC", split="2026")
    vlc_sentences = extract_sentences(ds_vlc, is_valid_legal, TARGET_PER_DOMAIN, "Legal")
    save_sentences(vlc_sentences, join(base_dir, "ws_sentences_vlc.txt"))

    # --- News (UVN-1) ---
    print(f"\n[2/5] Fetching news sentences (target: {TARGET_PER_DOMAIN})...")
    ds_uvn = load_dataset("undertheseanlp/UVN-1", split="train")
    uvn_sentences = extract_sentences(ds_uvn, is_valid_news, TARGET_PER_DOMAIN, "News")
    save_sentences(uvn_sentences, join(base_dir, "ws_sentences_uvn.txt"))

    # --- Wikipedia (UVW-2026) ---
    print(f"\n[3/5] Fetching Wikipedia sentences (target: {TARGET_PER_DOMAIN})...")
    ds_uvw = load_dataset("undertheseanlp/UVW-2026", split="train")
    high_quality = [doc for doc in ds_uvw if (doc.get("quality_score") or 0) >= 5]
    print(f"  High-quality articles: {len(high_quality)}")
    uvw_sentences = extract_sentences(high_quality, is_valid_wiki, TARGET_PER_DOMAIN, "Wikipedia")
    save_sentences(uvw_sentences, join(base_dir, "ws_sentences_uvw.txt"))

    # --- Books (UVB-v0.1) ---
    print(f"\n[4/5] Fetching fiction sentences (target: {TARGET_PER_DOMAIN})...")
    print(f"[5/5] Fetching non-fiction sentences (target: {TARGET_PER_DOMAIN})...")
    ds_uvb = load_dataset("undertheseanlp/UVB-v0.1", split="train")

    fiction_books = []
    non_fiction_books = []
    for book in ds_uvb:
        genres = book.get("genres", [])
        rating = book.get("goodreads_rating", 0) or 0
        num_ratings = book.get("goodreads_num_ratings", 0) or 0
        quality_score = rating * min(num_ratings / 100, 10)
        book_type = classify_book(genres)
        book_info = {
            "title": book["title"],
            "content": book["content"],
            "quality_score": quality_score,
        }
        if book_type == "fiction":
            fiction_books.append(book_info)
        elif book_type == "non-fiction":
            non_fiction_books.append(book_info)

    fiction_books.sort(key=lambda x: x["quality_score"], reverse=True)
    non_fiction_books.sort(key=lambda x: x["quality_score"], reverse=True)
    print(f"  Fiction books: {len(fiction_books)}, Non-fiction books: {len(non_fiction_books)}")

    fiction_sentences = extract_book_sentences(fiction_books, TARGET_PER_DOMAIN, "Fiction")
    save_sentences(fiction_sentences, join(base_dir, "ws_sentences_uvb_f.txt"))

    nonfiction_sentences = extract_book_sentences(non_fiction_books, TARGET_PER_DOMAIN, "Non-fiction")
    save_sentences(nonfiction_sentences, join(base_dir, "ws_sentences_uvb_n.txt"))

    # --- Summary ---
    print("\n" + "=" * 60)
    print("Summary:")
    print(f"  Legal:       {len(vlc_sentences):,}")
    print(f"  News:        {len(uvn_sentences):,}")
    print(f"  Wikipedia:   {len(uvw_sentences):,}")
    print(f"  Fiction:     {len(fiction_sentences):,}")
    print(f"  Non-fiction: {len(nonfiction_sentences):,}")
    total = len(vlc_sentences) + len(uvn_sentences) + len(uvw_sentences) + len(fiction_sentences) + len(nonfiction_sentences)
    print(f"  Total:       {total:,}")


if __name__ == "__main__":
    main()