Fix bug when extra=0
Fix bug when extra=0

gabrielegiannini/torch-rnn-repo,phanhuy1502/FYP,jcjohnson/torch-rnn,dgcrouse/torch-rnn,phanhuy1502/FYP,oneyanshi/transcend-exe,tmp6154/torch-rnn,spaceraccoon/bilabot,antihutka/torch-rnn