biye2014/lgr — pull request #2 by biye2014 (2014-09-19 13:52:58+00:00)
Title: Viterbi search

re-designed backward_bigram_lattice and the viterbi search based on that data structure

backward_bigram_lattice, or b for short now maps to valid bigrams or word that start and ends at specific positions.
for i,j,k that are valid in the list/dictionary, b[i-1][j][k] maps to --> bigram (sent[k:j], [j:i]) if j!=0
b[i-1][0], if exist maps to ---> bigram (START_symbol, word sent[j:i])
(constraint: 00 exit k such that 0 word [i:j]
(constraint: 0