Project Notes

H-Index II

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Description

tab: English
 
<p>Given an array of integers <code>citations</code> where <code>citations[i]</code> is the number of citations a researcher received for their <code>i<sup>th</sup></code> paper and <code>citations</code> is sorted in <strong>non-descending order</strong>, return <em>the researcher&#39;s h-index</em>.</p>
 
<p>According to the <a href="https://en.wikipedia.org/wiki/H-index" target="_blank">definition of h-index on Wikipedia</a>: The h-index is defined as the maximum value of <code>h</code> such that the given researcher has published at least <code>h</code> papers that have each been cited at least <code>h</code> times.</p>
 
<p>You must write an algorithm that runs in logarithmic time.</p>
 
<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
 
<pre>
<strong>Input:</strong> citations = [0,1,3,5,6]
<strong>Output:</strong> 3
<strong>Explanation:</strong> [0,1,3,5,6] means the researcher has 5 papers in total and each of them had received 0, 1, 3, 5, 6 citations respectively.
Since the researcher has 3 papers with at least 3 citations each and the remaining two with no more than 3 citations each, their h-index is 3.
</pre>
 
<p><strong class="example">Example 2:</strong></p>
 
<pre>
<strong>Input:</strong> citations = [1,2,100]
<strong>Output:</strong> 2
</pre>
 
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>
 
<ul>
	<li><code>n == citations.length</code></li>
	<li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= citations[i] &lt;= 1000</code></li>
	<li><code>citations</code> is sorted in <strong>ascending order</strong>.</li>
</ul>
 
 
 
> [!tip]- Hint 1
> 
> Expected runtime complexity is in <i>O</i>(log <i>n</i>) and the input is sorted.
 
 
---
 
[submissions](https://leetcode.com/problems/h-index-ii/submissions/) | [solutions](https://leetcode.com/problems/h-index-ii/solutions/)
 
 
tab: 中文
 
<p>给你一个整数数组 <code>citations</code> ，其中 <code>citations[i]</code> 表示研究者的第 <code>i</code> 篇论文被引用的次数，<code>citations</code> 已经按照&nbsp;<strong>非降序排列&nbsp;</strong>。计算并返回该研究者的 h<strong><em>&nbsp;</em></strong>指数。</p>
 
<p><a href="https://baike.baidu.com/item/h-index/3991452?fr=aladdin" target="_blank">h 指数的定义</a>：h 代表“高引用次数”（high citations），一名科研人员的 <code>h</code> 指数是指他（她）的 （<code>n</code> 篇论文中）<strong>至少&nbsp;</strong>有 <code>h</code> 篇论文分别被引用了<strong>至少</strong> <code>h</code> 次。</p>
 
<p>请你设计并实现对数时间复杂度的算法解决此问题。</p>
 
<p>&nbsp;</p>
 
<p><strong class="example">示例 1：</strong></p>
 
<pre>
<strong>输入：</strong><code>citations = [0,1,3,5,6]</code>
<strong>输出：</strong><code>3</code>
<strong>解释：</strong>给定数组表示研究者总共有 <code>5</code> 篇论文，每篇论文相应的被引用了 <code>0, 1, 3, 5, 6</code> 次。
&nbsp;    由于研究者有<code>3</code>篇论文每篇<strong> 至少 </strong>被引用了 <code>3</code> 次，其余两篇论文每篇被引用<strong> 不多于</strong> <code>3</code> 次，所以她的<em> h </em>指数是 <code>3</code> 。</pre>
 
<p><strong class="example">示例 2：</strong></p>
 
<pre>
<strong>输入：</strong><code>citations = [1,2,100]</code>
<strong>输出：</strong><code>2</code>
</pre>
 
<p>&nbsp;</p>
 
<p><strong>提示：</strong></p>
 
<ul>
	<li><code>n == citations.length</code></li>
	<li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= citations[i] &lt;= 1000</code></li>
	<li><code>citations</code> 按 <strong>升序排列</strong></li>
</ul>
 
 
 
> [!tip]- 提示 1
> 
> Expected runtime complexity is in <i>O</i>(log <i>n</i>) and the input is sorted.
 
 
---
 
[提交记录](https://leetcode.cn/problems/h-index-ii/submissions/) | [题解](https://leetcode.cn/problems/h-index-ii/solution/)

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