K-way merge - Python way

Re-sorting with sorted() in #2 defeats the purpose of the k-way merge, you may as well just materialize all the lists and sort them.<p>I didn't know about heapq.merge before, that seems like an efficient way to go. Usually when I do k-way merges it's over a data stream, so I almost always want an iterator.

<p><pre><code> &#62;&#62;&#62; from heapq import merge &#62;&#62;&#62; def kmerge(*lists): ... return merge(*map(sorted, lists)) ... &#62;&#62;&#62; list(kmerge([1,2,3],[6,5,4],[2,2])) [1, 2, 2, 2, 3, 4, 5, 6]</code></pre>