leetcode-visual/T033-binary-search-in-rotated-sorted-array.html at main · houbb/leetcode-visual · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8" />
  <title>LeetCode 033 动画演示</title>
  <style>
    body {
      font-family: sans-serif;
      background: #f8f9fa;
      padding: 2rem;
    }
    h1 {
      text-align: center;
      margin-bottom: 1rem;
    }
    .input-section {
      text-align: center;
      margin-bottom: 1rem;
    }
    input {
      padding: 0.5rem;
      margin: 0.25rem;
      width: 250px;
    }
    button {
      padding: 0.5rem 1rem;
      margin-top: 0.5rem;
      background-color: #007bff;
      color: white;
      border: none;
      border-radius: 5px;
      cursor: pointer;
    }
    .array-container {
      display: flex;
      justify-content: center;
      flex-wrap: wrap;
      margin: 2rem auto;
    }
    .box {
      width: 50px;
      height: 50px;
      line-height: 50px;
      margin: 5px;
      text-align: center;
      font-weight: bold;
      background-color: #e0e0e0;
      border-radius: 6px;
      position: relative;
      transition: 0.3s ease;
    }
    .box.left {
      background-color: #ffeaa7;
    }
    .box.mid {
      background-color: #fab1a0;
    }
    .box.right {
      background-color: #74b9ff;
    }
    .box.found {
      background-color: #55efc4;
    }
    .label {
      position: absolute;
      top: -20px;
      font-size: 12px;
      color: #555;
    }
    .log {
      max-width: 800px;
      margin: 2rem auto;
      font-size: 14px;
      background: #111;
      color: #00ff88;
      padding: 1rem;
      border-radius: 8px;
      border: 1px solid #333;
      max-height: 240px;
      overflow-y: auto;
      font-family: monospace;
    }
    .back-link {
      text-align: center;
      margin-top: 2rem;
    }
    .back-link a {
      color: #007bff;
      text-decoration: none;
      font-size: 16px;
    }
    .back-link a:hover {
      text-decoration: underline;
    }
  </style>
</head>
<body>

<h1>🔍 LeetCode 033 动画演示</h1>

<div class="input-section">
  <input type="text" id="numsInput" value="4,5,6,7,0,1,2" placeholder="输入数组，如 4,5,6,7,0,1,2" />
  <input type="number" id="targetInput" value="0" placeholder="目标值" />
  <br />
  <button onclick="startVisualization()">开始动画演示</button>
</div>

<div class="array-container" id="arrayContainer"></div>
<div class="log" id="log"></div>

<div class="back-link">
  <a href="index.html">⬅️ 返回首页</a>
</div>

<script>
  function sleep(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
  }

  function renderArray(nums, left, mid, right, targetIndex = -1) {
    const container = document.getElementById('arrayContainer');
    container.innerHTML = '';
    nums.forEach((num, idx) => {
      const div = document.createElement('div');
      div.className = 'box';
      div.textContent = num;

      if (idx === targetIndex) div.classList.add('found');
      else if (idx === left) {
        div.classList.add('left');
        div.innerHTML += `<div class="label">L</div>`;
      }
      else if (idx === mid) {
        div.classList.add('mid');
        div.innerHTML += `<div class="label">M</div>`;
      }
      else if (idx === right) {
        div.classList.add('right');
        div.innerHTML += `<div class="label">R</div>`;
      }

      container.appendChild(div);
    });
  }

  async function findPivotVisual(nums, logEl) {
    let left = 0, right = nums.length - 1;

    if (nums[left] < nums[right]) {
      logEl.innerHTML += `数组未旋转，返回 0<br>`;
      renderArray(nums, left, left, right);
      await sleep(800);
      return 0;
    }

    while (left <= right) {
      let mid = Math.floor((left + right) / 2);
      renderArray(nums, left, mid, right);
      logEl.innerHTML += `查找旋转点: L=${left}, M=${mid}, R=${right}<br>`;
      await sleep(800);

      if (mid < nums.length - 1 && nums[mid] > nums[mid + 1]) {
        logEl.innerHTML += `找到旋转点 at index ${mid}<br>`;
        return mid;
      }
      if (nums[mid] >= nums[left]) {
        left = mid + 1;
      } else {
        right = mid - 1;
      }
    }
    return -1;
  }

  async function binarySearchVisual(nums, target, left, right, logEl) {
    while (left <= right) {
      const mid = Math.floor((left + right) / 2);
      renderArray(nums, left, mid, right);
      logEl.innerHTML += `二分查找: L=${left}, M=${mid}, R=${right}<br>`;
      await sleep(800);
      if (nums[mid] === target) {
        renderArray(nums, -1, -1, -1, mid);
        logEl.innerHTML += `✅ 找到目标值 ${target} at index ${mid}<br>`;
        return mid;
      } else if (nums[mid] < target) {
        left = mid + 1;
      } else {
        right = mid - 1;
      }
    }
    logEl.innerHTML += `❌ 未找到目标值 ${target}<br>`;
    return -1;
  }

  async function startVisualization() {
    const nums = document.getElementById('numsInput').value.split(',').map(Number);
    const target = parseInt(document.getElementById('targetInput').value);
    const log = document.getElementById('log');
    log.innerHTML = '';

    const pivot = await findPivotVisual(nums, log);

    let result = -1;
    if (pivot === -1 || nums[0] <= target) {
      result = await binarySearchVisual(nums, target, 0, pivot === -1 ? nums.length - 1 : pivot, log);
    } else {
      result = await binarySearchVisual(nums, target, pivot + 1, nums.length - 1, log);
    }
  }
</script>

</body>
</html>