擅长:python、mysql、java
<p>一种方法是构建一个以列2数据为关键字的字典:</p>
<pre><code>from collections import defaultdict #defaultdict will save a line or two of code
d = defaultdict(list) # goal is for d to look like {'EEE':['rs001', 'rs008', ...
for line in file('data.txt', 'r'):
v, k = line.strip().split()
d[k].append(v)
for k, v in d.iteritems(): # print d as the strings you want
print ' '.join(v+[k])
</code></pre>
<p>这种方法的优点是不需要将第2列的术语组合在一起(尽管问题中没有直接指定第2列是否预先分组)。在</p>