擅长:python、mysql、java
<p>仅在Python2.7和3.1及以上:</p>
<pre><code>def ffs(x):
"""Returns the index, counting from 0, of the
least significant set bit in `x`.
"""
return (x&-x).bit_length()-1
</code></pre>
<p>示例:</p>
<pre><code>>>> ffs(136)
3
</code></pre>