192 lines
7.1 KiB
HTML
192 lines
7.1 KiB
HTML
|
<!DOCTYPE html>
|
|||
|
|
<html lang="zh-Hans">
|
|||
|
|
<head>
|
|||
|
|
<meta charset="UTF-8">
|
|||
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|||
|
|
<title>042. 将有序数组转换为二叉搜索树 – 图解</title>
|
|||
|
|
<link rel="stylesheet" href="../shared/style.css">
|
|||
|
|
<style>
|
|||
|
|
/* page-specific overrides */
|
|||
|
|
.vis-area { min-height: 120px; padding: 16px 0; }
|
|||
|
|
.code-section { margin-top: 16px; }
|
|||
|
|
</style>
|
|||
|
|
</head>
|
|||
|
|
<body>
|
|||
|
|
<div class="container">
|
|||
|
|
<h1>🟢 042. 将有序数组转换为二叉搜索树 <span class="badge easy">简单</span></h1>
|
|||
|
|
<p class="subtitle">分类：二叉树 ｜ LeetCode Hot 100</p>
|
|||
|
|
|
|||
|
|
<!-- 控制面板 -->
|
|||
|
|
<div class="controls" id="controls">
|
|||
|
|
<label for="inputArea">输入：</label>
|
|||
|
|
<input type="text" id="inputArea" placeholder="默认示例，可自定义">
|
|||
|
|
<button id="applyBtn" class="primary">生成图解</button>
|
|||
|
|
<select id="exampleSelect"></select>
|
|||
|
|
<span style="flex:1"></span>
|
|||
|
|
<button id="prevBtn">◀ 上一步</button>
|
|||
|
|
<button id="nextBtn">下一步 ▶</button>
|
|||
|
|
<button id="jumpBtn">⏭ 跳到结果</button>
|
|||
|
|
<button id="autoBtn">自动播放</button>
|
|||
|
|
<button id="resetBtn">重置</button>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<!-- 步骤流水线 -->
|
|||
|
|
<div class="pipeline" id="pipeline"></div>
|
|||
|
|
|
|||
|
|
<!-- 提示条 -->
|
|||
|
|
<div class="hint info" id="hintBox">
|
|||
|
|
<span id="stepInfo"></span><br>
|
|||
|
|
<span id="hintText"></span>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<!-- 可视化面板 -->
|
|||
|
|
<div class="panels">
|
|||
|
|
<div class="panel" id="mainPanel">
|
|||
|
|
<h3>📊 可视化</h3>
|
|||
|
|
<div class="vis-area" id="vizArea">点击「生成图解」开始</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="panel-grid">
|
|||
|
|
<div class="panel" id="detailPanel">
|
|||
|
|
<h3>📝 当前步骤详情</h3>
|
|||
|
|
<div id="detailContent">等待开始...</div>
|
|||
|
|
</div>
|
|||
|
|
<div class="panel" id="resultPanel">
|
|||
|
|
<h3>✅ 结果</h3>
|
|||
|
|
<div id="resultContent">等待完成...</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<!-- 代码 -->
|
|||
|
|
<div class="panel code-section">
|
|||
|
|
<h3>💻 参考代码（Python）</h3>
|
|||
|
|
<div id="codeArea"></div>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<footer>Powered by QwenPaw · 图解算法 · LeetCode Hot 100</footer>
|
|||
|
|
</div>
|
|||
|
|
|
|||
|
|
<script src="../shared/algo-viz.js"></script>
|
|||
|
|
<script>
|
|||
|
|
"use strict";
|
|||
|
|
(function() {
|
|||
|
|
// ========== Algorithm Logic ==========
|
|||
|
|
|
|||
|
|
function arrayToTree(arr) {
|
|||
|
|
if (!arr || arr.length === 0) return null;
|
|||
|
|
let idCtr = 0;
|
|||
|
|
const nodes = arr.map(v => v === null ? null : {val: v, left: null, right: null, _id: 'n' + (idCtr++)});
|
|||
|
|
for (let i = 0; i < nodes.length; i++) {
|
|||
|
|
if (!nodes[i]) continue;
|
|||
|
|
const li = 2*i+1, ri = 2*i+2;
|
|||
|
|
if (li < nodes.length) nodes[i].left = nodes[li];
|
|||
|
|
if (ri < nodes.length) nodes[i].right = nodes[ri];
|
|||
|
|
}
|
|||
|
|
return nodes[0];
|
|||
|
|
}
|
|||
|
|
function treeToArray(root) {
|
|||
|
|
if (!root) return [];
|
|||
|
|
const res = [], q = [root];
|
|||
|
|
while (q.length) {
|
|||
|
|
const n = q.shift();
|
|||
|
|
if (n === null) { res.push(null); continue; }
|
|||
|
|
res.push(n.val); q.push(n.left, n.right);
|
|||
|
|
}
|
|||
|
|
while (res.length && res[res.length-1] === null) res.pop();
|
|||
|
|
return res;
|
|||
|
|
}
|
|||
|
|
function deepClone(node) {
|
|||
|
|
if (!node) return null;
|
|||
|
|
return {val: node.val, _id: node._id, left: deepClone(node.left), right: deepClone(node.right)};
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
const examples = [
|
|||
|
|
{input: [-10,-3,0,5,9], label: '示例1: [-10,-3,0,5,9]'},
|
|||
|
|
{input: [1,3], label: '示例2: [1,3]'},
|
|||
|
|
{input: [1,2,3,4], label: '示例3: [1,2,3,4]'},
|
|||
|
|
];
|
|||
|
|
let nums, steps, stepCtrl, builtRoot;
|
|||
|
|
let idCtr;
|
|||
|
|
|
|||
|
|
function buildSteps(arr) {
|
|||
|
|
nums = [...arr]; steps = []; idCtr = 0;
|
|||
|
|
steps.push({stage:'init', hl:{}, lo:0, hi:arr.length-1, mid:-1, msg:'二分递归构造平衡 BST：取中间元素为根'});
|
|||
|
|
|
|||
|
|
function build(lo, hi) {
|
|||
|
|
if (lo > hi) return null;
|
|||
|
|
const mid = Math.floor((lo + hi) / 2);
|
|||
|
|
const node = {val: arr[mid], _id: 'n' + (idCtr++), left: null, right: null};
|
|||
|
|
const hl = {};
|
|||
|
|
for (let i = lo; i <= hi; i++) hl[i] = i === mid ? 'orange' : 'blue';
|
|||
|
|
steps.push({stage:'select', hl, mid, lo, hi, msg:`范围 [${lo},${hi}]，mid=${mid}，nums[${mid}]=${arr[mid]} 作为根`});
|
|||
|
|
node.left = build(lo, mid - 1);
|
|||
|
|
node.right = build(mid + 1, hi);
|
|||
|
|
return node;
|
|||
|
|
}
|
|||
|
|
builtRoot = build(0, arr.length - 1);
|
|||
|
|
steps.push({stage:'done', hl:{}, lo:0, hi:arr.length-1, mid:-1, msg:'构造完成！'});
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
function render(step) {
|
|||
|
|
const s = steps[step];
|
|||
|
|
let viz = '<div style="margin-bottom:8px;"><b>有序数组：</b></div>';
|
|||
|
|
viz += renderArray(nums, {highlights: s.hl || {}});
|
|||
|
|
if (s.lo !== undefined) {
|
|||
|
|
viz += `<div style="margin-top:4px;font-size:13px;color:var(--text-secondary);">范围: [${s.lo}, ${s.hi}]${s.mid>=0 ? ' mid='+s.mid+' 值='+nums[s.mid] : ''}</div>`;
|
|||
|
|
}
|
|||
|
|
if (builtRoot) {
|
|||
|
|
viz += '<div style="margin-top:12px;"><b>构造中的 BST：</b></div>';
|
|||
|
|
viz += renderBinaryTree(builtRoot, {highlights: {}});
|
|||
|
|
}
|
|||
|
|
$('vizArea').innerHTML = viz;
|
|||
|
|
$('detailContent').innerHTML = '<div class="calc-block">' + s.msg + '</div>';
|
|||
|
|
if (s.stage === 'done') {
|
|||
|
|
$('resultContent').innerHTML = `<div class="final-answer">BST 构建完成 = <b>[${treeToArray(builtRoot)}]</b></div>`;
|
|||
|
|
}
|
|||
|
|
$('hintText').textContent = s.msg;
|
|||
|
|
const stages = ['init→初始化','select→选中间','done→完成'];
|
|||
|
|
$('pipeline').innerHTML = stages.map(st => {
|
|||
|
|
const [k,l] = st.split('→');
|
|||
|
|
return `<span class="pipe-step ${s.stage===k?'active':''}">${l}</span>`;
|
|||
|
|
}).join('<i>→</i>');
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
function init() {
|
|||
|
|
const sel = $('exampleSelect');
|
|||
|
|
examples.forEach((e,i) => { sel.innerHTML += `<option value="${i}">${e.label}</option>`; });
|
|||
|
|
$('inputArea').value = '[-10,-3,0,5,9]';
|
|||
|
|
buildSteps(examples[0].input);
|
|||
|
|
stepCtrl = new StepController({onStep: render});
|
|||
|
|
stepCtrl.setSteps(steps.map((_,i)=>i));
|
|||
|
|
$('stepInfo').textContent = '步骤 1 / ' + steps.length;
|
|||
|
|
stepCtrl.onStep = (idx) => { render(idx); $('stepInfo').textContent = `步骤 ${idx+1} / ${steps.length}`; };
|
|||
|
|
$('applyBtn').onclick = () => {
|
|||
|
|
try { const arr = JSON.parse($('inputArea').value); buildSteps(arr); stepCtrl.setSteps(steps.map((_,i)=>i)); render(0); $('stepInfo').textContent = '步骤 1 / ' + steps.length; }
|
|||
|
|
catch(e) { alert('请输入合法升序数组'); }
|
|||
|
|
};
|
|||
|
|
$('exampleSelect').onchange = () => {
|
|||
|
|
const e = examples[parseInt($('exampleSelect').value)];
|
|||
|
|
$('inputArea').value = JSON.stringify(e.input);
|
|||
|
|
buildSteps(e.input); stepCtrl.setSteps(steps.map((_,i)=>i)); render(0);
|
|||
|
|
};
|
|||
|
|
$('prevBtn').onclick = () => stepCtrl.prev();
|
|||
|
|
$('nextBtn').onclick = () => stepCtrl.next();
|
|||
|
|
$('jumpBtn').onclick = () => stepCtrl.jumpToEnd();
|
|||
|
|
$('autoBtn').onclick = () => { const on = stepCtrl.toggleAuto(); $('autoBtn').textContent = on ? '暂停' : '自动播放'; };
|
|||
|
|
$('resetBtn').onclick = () => { stepCtrl.reset(); $('autoBtn').textContent = '自动播放'; };
|
|||
|
|
}
|
|||
|
|
init();
|
|||
|
|
$('codeArea').innerHTML = renderCode(`def sortedArrayToBST(nums):
|
|||
|
|
def build(lo, hi):
|
|||
|
|
if lo > hi: return None
|
|||
|
|
mid = (lo + hi) // 2
|
|||
|
|
root = TreeNode(nums[mid])
|
|||
|
|
root.left = build(lo, mid - 1)
|
|||
|
|
root.right = build(mid + 1, hi)
|
|||
|
|
return root
|
|||
|
|
return build(0, len(nums) - 1)`, {lang:'Python'});
|
|||
|
|
|
|||
|
|
})();
|
|||
|
|
</script>
|
|||
|
|
</body>
|
|||
|
|
</html>
|