擅长:python、mysql、java
<p>如果我需要这样的东西,我通常会成对迭代:</p>
<pre><code>from itertools import tee, izip
def pairwise(iterable):
"""Iterate in pairs
>>> list(pairwise([0, 1, 2, 3]))
[(0, 1), (1, 2), (2, 3)]
>>> tuple(pairwise([])) == tuple(pairwise('x')) == ()
True
"""
a, b = tee(iterable)
next(b, None)
return izip(a, b)
</code></pre>
<p>用法如下:</p>
<pre><code>for left, right in pairwise(iterable):
...
</code></pre>