擅长:python、mysql、java
<p>只有值不在<code>seen</code>中时,才能创建一组可见值并添加元组:</p>
<pre><code>>>> lst
[(0.10507038451969995,
'Deadly stampede in Shanghai - Emergency personnel help victims.'),
(0.078586381821416265,
'Deadly stampede in Shanghai - Police and medical staff help injured people after the stampede.'),
(0.072031446647399661, '- Emergency personnel help victims.'),
(0.072031446647399661, 'Emergency personnel help victims.')]
>>> seen = set()
>>> result = []
>>> for a, b in lst:
... if not a in seen:
... seen.add(a)
... result.append((a, b))
>>> print result
[(0.10507038451969995, 'Deadly stampede in Shanghai - Emergency personnel help victims.'),
(0.07858638182141627, 'Deadly stampede in Shanghai - Police and medical staff help injured people after the stampede.'),
(0.07203144664739966, '- Emergency personnel help victims.')]
</code></pre>
<p>这里有另一种理解方法:</p>
^{pr2}$