mirror of
				https://gitee.com/coder-xiaomo/leetcode-problemset
				synced 2025-11-04 11:43:12 +08:00 
			
		
		
		
	
		
			
				
	
	
		
			46 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			46 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
<p>给定一个正整数 <code>n</code>,编写一个函数,获取一个正整数的二进制形式并返回其二进制表达式中 <span data-keyword="set-bit">设置位</span> 的个数(也被称为<a href="https://baike.baidu.com/item/%E6%B1%89%E6%98%8E%E9%87%8D%E9%87%8F" target="_blank">汉明重量</a>)。</p>
 | 
						||
 | 
						||
<p> </p>
 | 
						||
 | 
						||
<p><strong>示例 1:</strong></p>
 | 
						||
 | 
						||
<pre>
 | 
						||
<strong>输入:</strong>n = 11
 | 
						||
<strong>输出:</strong>3
 | 
						||
<strong>解释:</strong>输入的二进制串 <code><strong>1011</strong> 中,共有 3 个设置位。</code>
 | 
						||
</pre>
 | 
						||
 | 
						||
<p><strong>示例 2:</strong></p>
 | 
						||
 | 
						||
<pre>
 | 
						||
<strong>输入:</strong>n = 128
 | 
						||
<strong>输出:</strong>1
 | 
						||
<strong>解释:</strong>输入的二进制串 <strong>10000000</strong> 中,共有 1 个设置位。
 | 
						||
</pre>
 | 
						||
 | 
						||
<p><strong>示例 3:</strong></p>
 | 
						||
 | 
						||
<pre>
 | 
						||
<strong>输入:</strong>n = 2147483645
 | 
						||
<strong>输出:</strong>30
 | 
						||
<strong>解释:</strong>输入的二进制串 <strong>1111111111111111111111111111101</strong> 中,共有 30 个设置位。</pre>
 | 
						||
 | 
						||
<p> </p>
 | 
						||
 | 
						||
<p><strong>提示:</strong></p>
 | 
						||
 | 
						||
<ul>
 | 
						||
	<li><code>1 <= n <= 2<sup>31</sup> - 1</code></li>
 | 
						||
</ul>
 | 
						||
 | 
						||
<ul>
 | 
						||
</ul>
 | 
						||
 | 
						||
<p> </p>
 | 
						||
 | 
						||
<p><strong>进阶</strong>:</p>
 | 
						||
 | 
						||
<ul>
 | 
						||
	<li>如果多次调用这个函数,你将如何优化你的算法?</li>
 | 
						||
</ul>
 |