[moses-smt/mosesdecoder] ac045a: Speed up N-gram counts when running extractor.

[GitHub <no...@gi...>]

  Branch: refs/heads/master
  Home:   https://github.com/moses-smt/mosesdecoder
  Commit: ac045a11c1f0e1d4ae25f0db47061113fc3ae2e1
      https://github.com/moses-smt/mosesdecoder/commit/ac045a11c1f0e1d4ae25f0db47061113fc3ae2e1
  Author: Tetsuo Kiso <tet...@is...>
  Date:   2012-12-06 (Thu, 06 Dec 2012)

  Changed paths:
    M mert/BleuScorer.cpp
    M mert/Ngram.h

  Log Message:
  -----------
  Speed up N-gram counts when running extractor.

By replacing std::map with boost::unordered_map.

Runtime of extractor on 100-best lists of 2679 sentences:

Before:
real    0m35.314s
user    0m34.030s
sys     0m1.280s

Ater:
real    0m26.729s
user    0m25.420s
sys     0m1.310s