if (!text) return '';

return text

.replace(/\r\n/g, ' ')

.replace(/\n/g, ' ')

.replace(/\r/g, ' ')

.replace(/\t/g, ' ');

let html = code

.replace(/&/g, '&')

.replace(/</g, '&lt;')

.replace(/>/g, '&gt;');

const keywords = ['const', 'let', 'var', 'function', 'return', 'if', 'else', 'while', 'for', 'break', 'continue', 'new', 'this', 'null', 'true', 'false', 'typeof', 'instanceof', 'class', 'extends', 'constructor', 'static', 'get', 'set', 'async', 'await', 'try', 'catch', 'throw', 'finally', 'of', 'in'];

const builtins = ['Math', 'Array', 'Object', 'String', 'Number', 'Boolean', 'Map', 'Set', 'console', 'prototype', 'length', 'push', 'pop', 'shift', 'unshift', 'slice', 'splice', 'concat', 'join', 'reverse', 'sort', 'filter', 'map', 'reduce', 'forEach', 'find', 'findIndex', 'includes', 'indexOf', 'fill', 'from', 'floor', 'ceil', 'max', 'min', 'abs', 'log', 'pow', 'sqrt', 'random', 'hasOwnProperty', 'toString', 'valueOf', 'substring', 'substr', 'split', 'trim', 'replace', 'match', 'test', 'exec', 'has', 'get', 'set', 'delete', 'add', 'clear', 'keys', 'values', 'entries', 'size', 'isEmpty', 'TreeNode', 'ListNode'];

html = html.replace(/(\/\/[^\n]*)/g, '<span style="color:#6A9955;">$1</span>');

html = html.replace(/(\/\*[\s\S]*?\*\/)/g, '<span style="color:#6A9955;">$1</span>');

html = html.replace(/(&quot;[^&]*?&quot;|'[^']*?'|`[^`]*?`)/g, '<span style="color:#CE9178;">$1</span>');

html = html.replace(/\b(\d+\.?\d*)\b/g, '<span style="color:#B5CEA8;">$1</span>');

for (const kw of keywords) {

const regex = new RegExp(`\\b(${kw})\\b`, 'g');

html = html.replace(regex, '<span style="color:#C586C0;">$1</span>');

}

for (const builtin of builtins) {

const regex = new RegExp(`\\b(${builtin})\\b`, 'g');

html = html.replace(regex, '<span style="color:#4EC9B0;">$1</span>');

}

html = html.replace(/\b([a-zA-Z_$][a-zA-Z0-9_$]*)\s*\(/g, '<span style="color:#DCDCAA;">$1</span>(');

html = html.replace(/=&gt;/g, '<span style="color:#C586C0;">=&gt;</span>');

return html;

if (!code) return '';

const highlighted = highlightJS(code.trim());

const withBreaks = highlighted

.replace(/\r\n/g, '<br>')

.replace(/\n/g, '<br>')

.replace(/\r/g, '<br>')

.replace(/\t/g, ' ');

return `<div style='background:#1e1e1e; color:#d4d4d4; padding:15px; border-radius:8px; font-family:Consolas,Monaco,"Courier New",monospace; font-size:13px; line-height:1.5; overflow-x:auto; text-align:left; white-space:pre-wrap; border:1px solid #333;'><code style='font-family:inherit;'>\`\`\`javascript<br>${withBreaks}<br>\`\`\`</code></div>`;

const questions = [];

const lines = content.split('\n');

let inBinaryTreeSection = false;

let currentCategory = '';

for (let i = 0; i < lines.length; i++) {

const line = lines[i];

// 检测二叉树章节开始

if (line.includes('## 二、 二叉树')) {

inBinaryTreeSection = true;

continue;

}

// 检测二叉树章节结束（下一个二级标题）

if (inBinaryTreeSection && line.match(/^## [三四五六七八九十]/)) {

break;

}

if (!inBinaryTreeSection) continue;

const categoryMatch = line.match(/^\*\*(.+)\*\*$/);

if (categoryMatch) {

currentCategory = categoryMatch[1];

continue;

}

// 解析题目行

const questionMatch = line.match(/^- \[(.+?)\]\((.+?)\)\s*\((\w+)\)(?:\s*-\s*\*(.+?)\*)?/);

if (questionMatch) {

const title = questionMatch[1];

const link = questionMatch[2];

const difficulty = questionMatch[3];

const tag = questionMatch[4] || '';

let description = '';

if (i + 1 < lines.length && lines[i + 1].trim().startsWith('>')) {

description = lines[i + 1].trim().replace(/^>\s*/, '');

}

questions.push({ title, link, difficulty, tag, category: currentCategory, description });

}

}

return questions;

const solutions = {};

const lines = content.split('\n');

let currentQuestionNum = null;

let currentCode = '';

let inCodeBlock = false;

for (let i = 0; i < lines.length; i++) {

const line = lines[i];

// 检测题目标题 - 多种格式

// [102. 二叉树的层序遍历]

// [236. 二叉树的最近公共祖先]

// [LCR 143. 树的子结构] -> 对应剑指 Offer 26

const titleMatch = line.match(/\[(\d+)[.．\s]/);

if (titleMatch) {

const num = titleMatch[1];

if (num) {

currentQuestionNum = num;

if (!solutions[currentQuestionNum]) {

solutions[currentQuestionNum] = [];

}

}

}

// 特殊处理剑指 Offer 题目

if (line.includes('LCR 143') || line.includes('树的子结构')) {

currentQuestionNum = '26'; // 剑指 Offer 26

if (!solutions[currentQuestionNum]) {

solutions[currentQuestionNum] = [];

}

}

if (line.trim().startsWith('```js') || line.trim().startsWith('```javascript')) {

inCodeBlock = true;

currentCode = '';

continue;

}

if (line.trim() === '```' && inCodeBlock) {

inCodeBlock = false;

if (currentQuestionNum && currentCode.trim()) {

solutions[currentQuestionNum].push(currentCode.trim());

}

currentCode = '';

continue;

}

if (inCodeBlock) {

currentCode += line + '\n';

}

}

return solutions;

const cards = [];

for (const q of questions) {

// 从题目标题中提取题号

const numMatch = q.title.match(/^(\d+)/);

let questionNum = numMatch ? numMatch[1] : null;

// 特殊处理剑指 Offer 题目

if (q.title.includes('剑指 Offer 26') || q.title.includes('树的子结构')) {

questionNum = '26';

}

// 正面 - 题目卡片 (绿色主题，适合二叉树)

let front = `<div style='background:linear-gradient(135deg,#11998e 0%,#38ef7d 100%); padding:20px; border-radius:12px; color:white;'>`;

front += `<h2 style='margin:0 0 15px 0; font-size:20px;'>🌳 ${escapeForAnki(q.title)}</h2>`;

const diffColor = q.difficulty === 'Easy' ? '#4CAF50' : q.difficulty === 'Medium' ? '#FF9800' : '#f44336';

const diffBg = q.difficulty === 'Easy' ? '#E8F5E9' : q.difficulty === 'Medium' ? '#FFF3E0' : '#FFEBEE';

front += `<p style='margin:10px 0;'><span style='background:${diffBg}; color:${diffColor}; padding:4px 12px; border-radius:12px; font-weight:bold; font-size:12px;'>${q.difficulty}</span>`;

if (q.tag) front += ` <span style='background:rgba(255,255,255,0.2); padding:4px 12px; border-radius:12px; font-size:12px;'>${escapeForAnki(q.tag)}</span>`;

if (q.category) front += ` <span style='background:rgba(255,255,255,0.2); padding:4px 12px; border-radius:12px; font-size:12px;'>${escapeForAnki(q.category)}</span>`;

front += `</p>`;

if (q.description) {

front += `<div style='background:rgba(255,255,255,0.15); padding:15px; border-radius:8px; margin:15px 0; font-size:14px; line-height:1.6;'>${escapeForAnki(q.description)}</div>`;

}

front += `<p style='margin:15px 0 0 0;'><a href='${q.link}' style='color:#fff; text-decoration:underline;'>📎 LeetCode 链接</a></p>`;

front += `</div>`;

// 反面 - 答案

let back = `<div style='padding:15px; background:#f5f5f5; border-radius:12px;'>`;

back += `<h3 style='color:#333; margin:0 0 15px 0; border-bottom:2px solid #11998e; padding-bottom:10px;'>💡 解题代码</h3>`;

if (questionNum && solutions[questionNum] && solutions[questionNum].length > 0) {

const codes = solutions[questionNum];

codes.forEach((code, idx) => {

if (codes.length > 1) {

back += `<p style='color:#11998e; font-weight:bold; margin:15px 0 10px 0;'>📝 解法 ${idx + 1}</p>`;

}

back += formatCodeForAnki(code);

if (idx < codes.length - 1) back += `<hr style='border:none; border-top:1px dashed #ccc; margin:20px 0;'>`;

});

} else {

back += `<p style='color:#999; font-style:italic; text-align:center; padding:20px;'>暂无代码答案，请参考 LeetCode 官方题解</p>`;

}

back += `</div>`;

cards.push({ front, back, title: q.title });

}

return cards;

const lines = cards.map(card => {

const front = card.front.replace(/[\r\n]+/g, ' ').replace(/\t/g, ' ');

const back = card.back.replace(/[\r\n]+/g, ' ').replace(/\t/g, ' ');

return `${front}\t${back}`;

});

fs.writeFileSync(outputPath, lines.join('\n'), 'utf8');