Project Notes

Search in Rotated Sorted Array

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Description

tab: English
 
<p>There is an integer array <code>nums</code> sorted in ascending order (with <strong>distinct</strong> values).</p>
 
<p>Prior to being passed to your function, <code>nums</code> is <strong>possibly left rotated</strong> at an unknown index <code>k</code> (<code>1 &lt;= k &lt; nums.length</code>) such that the resulting array is <code>[nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]]</code> (<strong>0-indexed</strong>). For example, <code>[0,1,2,4,5,6,7]</code> might be left rotated by&nbsp;<code>3</code>&nbsp;indices and become <code>[4,5,6,7,0,1,2]</code>.</p>
 
<p>Given the array <code>nums</code> <strong>after</strong> the possible rotation and an integer <code>target</code>, return <em>the index of </em><code>target</code><em> if it is in </em><code>nums</code><em>, or </em><code>-1</code><em> if it is not in </em><code>nums</code>.</p>
 
<p>You must write an algorithm with <code>O(log n)</code> runtime complexity.</p>
 
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> nums = [4,5,6,7,0,1,2], target = 0
<strong>Output:</strong> 4
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> nums = [4,5,6,7,0,1,2], target = 3
<strong>Output:</strong> -1
</pre><p><strong class="example">Example 3:</strong></p>
<pre><strong>Input:</strong> nums = [1], target = 0
<strong>Output:</strong> -1
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
 
<ul>
	<li><code>1 &lt;= nums.length &lt;= 5000</code></li>
	<li><code>-10<sup>4</sup> &lt;= nums[i] &lt;= 10<sup>4</sup></code></li>
	<li>All values of <code>nums</code> are <strong>unique</strong>.</li>
	<li><code>nums</code> is an ascending array that is possibly rotated.</li>
	<li><code>-10<sup>4</sup> &lt;= target &lt;= 10<sup>4</sup></code></li>
</ul>
 
 
 
---
 
[submissions](https://leetcode.com/problems/search-in-rotated-sorted-array/submissions/) | [solutions](https://leetcode.com/problems/search-in-rotated-sorted-array/solutions/)
 
 
tab: 中文
 
<p>整数数组 <code>nums</code> 按升序排列，数组中的值 <strong>互不相同</strong> 。</p>
 
<p>在传递给函数之前，<code>nums</code> 在预先未知的某个下标 <code>k</code>（<code>0 &lt;= k &lt; nums.length</code>）上进行了 <strong>向左旋转</strong>，使数组变为 <code>[nums[k], nums[k+1], ..., nums[n-1], nums[0], nums[1], ..., nums[k-1]]</code>（下标 <strong>从 0 开始</strong> 计数）。例如， <code>[0,1,2,4,5,6,7]</code> 下标&nbsp;<code>3</code>&nbsp;上向左旋转后可能变为&nbsp;<code>[4,5,6,7,0,1,2]</code> 。</p>
 
<p>给你 <strong>旋转后</strong> 的数组 <code>nums</code> 和一个整数 <code>target</code> ，如果 <code>nums</code> 中存在这个目标值 <code>target</code> ，则返回它的下标，否则返回&nbsp;<code>-1</code>&nbsp;。</p>
 
<p>你必须设计一个时间复杂度为 <code>O(log n)</code> 的算法解决此问题。</p>
 
<p>&nbsp;</p>
 
<p><strong>示例 1：</strong></p>
 
<pre>
<strong>输入：</strong>nums = [4,5,6,7,0,1,2], target = 0
<strong>输出：</strong>4
</pre>
 
<p><strong>示例&nbsp;2：</strong></p>
 
<pre>
<strong>输入：</strong>nums = [4,5,6,7,0,1,2], target = 3
<strong>输出：</strong>-1</pre>
 
<p><strong>示例 3：</strong></p>
 
<pre>
<strong>输入：</strong>nums = [1], target = 0
<strong>输出：</strong>-1
</pre>
 
<p>&nbsp;</p>
 
<p><strong>提示：</strong></p>
 
<ul>
	<li><code>1 &lt;= nums.length &lt;= 5000</code></li>
	<li><code>-10<sup>4</sup> &lt;= nums[i] &lt;= 10<sup>4</sup></code></li>
	<li><code>nums</code> 中的每个值都 <strong>独一无二</strong></li>
	<li>题目数据保证 <code>nums</code> 在预先未知的某个下标上进行了旋转</li>
	<li><code>-10<sup>4</sup> &lt;= target &lt;= 10<sup>4</sup></code></li>
</ul>
 
 
 
---
 
[提交记录](https://leetcode.cn/problems/search-in-rotated-sorted-array/submissions/) | [题解](https://leetcode.cn/problems/search-in-rotated-sorted-array/solution/)

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